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• What is a good solution to log the deletion of a row in MySQL?

  - by hobodave

  Background I am currently logging deletion of rows from my tickets table at the application level. When a user deletes a ticket the following SQL is executed: INSERT INTO alert_log (user_id, priority, priorityName, timestamp, message) VALUES (9, 4, 'WARN', NOW(), "TICKET: David A. deleted ticket #6 from Foo"); Please do not offer schema suggestions for the alert_log table. Fields: user_id - User id of the logged in user performing the deletion priority - Always 4 priorityName - Always 'WARN' timestamp - Always NOW() message - Format: "[NAMESPACE]: [FullName] deleted ticket #[TicketId] from [CompanyName]" NAMESPACE - Always TICKET FullName - Full name of user identified by user_id above TicketId - Primary key ID of the ticket being deleted CompanyName - Ticket has a Company via tickets.company_id Situation/Questions Obviously this solution does not work if a ticket is deleted manually from the mysql command line client. However, now I need to. The issues I'm having are as follows: Should I use a PROCEDURE, FUNCTION, or TRIGGER? -- Analysis: TRIGGER - I don't think this will work because I can't pass parameters to it, and it would trigger when my application deleted the row too. PROCEDURE or FUNCTION - Not sure. Should I return the number of deleted rows? If so, that would require a FUNCTION right? How should I account for the absence of a logged in user? -- Possibilities: Using either a PROC or FUNC, require the invoker to pass in a valid user_id Require the user to pass in a string with the name Use the CURRENT_USER - meh Hard code the FullName to just be "Database Administrator" Could the name be an optional parameter? I'm rather green when it comes to sprocs. Assuming I went with the PROC/FUNC approach, is it possible to outright restrict regular DELETE calls to this table, yet still allow users to call this PROC/FUNC to do the deletion for them? Ideally the solution is usable by my application as well, so that my code is DRY.

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• To ref or not to ref

  - by nmarun

  So the question is what is the point of passing a reference type along with the ref keyword? I have an Employee class as below: 1: public class Employee 2: { 3: public string FirstName { get; set; } 4: public string LastName { get; set; } 5:  6: public override string ToString() 7: { 8: return string.Format("{0}-{1}", FirstName, LastName); 9: } 10: } In my calling class, I say: 1: class Program 2: { 3: static void Main() 4: { 5: Employee employee = new Employee 6: { 7: FirstName = "John", 8: LastName = "Doe" 9: }; 10: Console.WriteLine(employee); 11: CallSomeMethod(employee); 12: Console.WriteLine(employee); 13: } 14:  15: private static void CallSomeMethod(Employee employee) 16: { 17: employee.FirstName = "Smith"; 18: employee.LastName = "Doe"; 19: } 20: }   After having a look at the code, you’ll probably say, Well, an instance of a class gets passed as a reference, so any changes to the instance inside the CallSomeMethod, actually modifies the original object. Hence the output will be ‘John-Doe’ on the first call and ‘Smith-Doe’ on the second. And you’re right: So the question is what’s the use of passing this Employee parameter as a ref? 1: class Program 2: { 3: static void Main() 4: { 5: Employee employee = new Employee 6: { 7: FirstName = "John", 8: LastName = "Doe" 9: }; 10: Console.WriteLine(employee); 11: CallSomeMethod(ref employee); 12: Console.WriteLine(employee); 13: } 14:  15: private static void CallSomeMethod(ref Employee employee) 16: { 17: employee.FirstName = "Smith"; 18: employee.LastName = "Doe"; 19: } 20: } The output is still the same: Ok, so is there really a need to pass a reference type using the ref keyword? I’ll remove the ‘ref’ keyword and make one more change to the CallSomeMethod method. 1: class Program 2: { 3: static void Main() 4: { 5: Employee employee = new Employee 6: { 7: FirstName = "John", 8: LastName = "Doe" 9: }; 10: Console.WriteLine(employee); 11: CallSomeMethod(employee); 12: Console.WriteLine(employee); 13: } 14:  15: private static void CallSomeMethod(Employee employee) 16: { 17: employee = new Employee 18: { 19: FirstName = "Smith", 20: LastName = "John" 21: }; 22: } 23: } In line 17 you’ll see I’ve ‘new’d up the incoming Employee parameter and then set its properties to new values. The output tells me that the original instance of the Employee class does not change. Huh? But an instance of a class gets passed by reference, so why did the values not change on the original instance or how do I keep the two instances in-sync all the times? Aah, now here’s the answer. In order to keep the objects in sync, you pass them using the ‘ref’ keyword. 1: class Program 2: { 3: static void Main() 4: { 5: Employee employee = new Employee 6: { 7: FirstName = "John", 8: LastName = "Doe" 9: }; 10: Console.WriteLine(employee); 11: CallSomeMethod(ref employee); 12: Console.WriteLine(employee); 13: } 14:  15: private static void CallSomeMethod(ref Employee employee) 16: { 17: employee = new Employee 18: { 19: FirstName = "Smith", 20: LastName = "John" 21: }; 22: } 23: } Viola! Now, to prove it beyond doubt, I said, let me try with another reference type: string. 1: class Program 2: { 3: static void Main() 4: { 5: string name = "abc"; 6: Console.WriteLine(name); 7: CallSomeMethod(ref name); 8: Console.WriteLine(name); 9: } 10:  11: private static void CallSomeMethod(ref string name) 12: { 13: name = "def"; 14: } 15: } The output was as expected, first ‘abc’ and then ‘def’ - proves the 'ref' keyword works here as well. Now, what if I remove the ‘ref’ keyword? The output should still be the same as the above right, since string is a reference type? 1: class Program 2: { 3: static void Main() 4: { 5: string name = "abc"; 6: Console.WriteLine(name); 7: CallSomeMethod(name); 8: Console.WriteLine(name); 9: } 10:  11: private static void CallSomeMethod(string name) 12: { 13: name = "def"; 14: } 15: } Wrong, the output shows ‘abc’ printed twice. Wait a minute… now how could this be? This is because string is an immutable type. This means that any time you modify an instance of string, new memory address is allocated to the instance. The effect is similar to ‘new’ing up the Employee instance inside the CallSomeMethod in the absence of the ‘ref’ keyword. Verdict: ref key came to the rescue and saved the planet… again!

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• JavaScript Class Patterns

  - by Liam McLennan

  To write object-oriented programs we need objects, and likely lots of them. JavaScript makes it easy to create objects: var liam = { name: "Liam", age: Number.MAX_VALUE }; But JavaScript does not provide an easy way to create similar objects. Most object-oriented languages include the idea of a class, which is a template for creating objects of the same type. From one class many similar objects can be instantiated. Many patterns have been proposed to address the absence of a class concept in JavaScript. This post will compare and contrast the most significant of them. Simple Constructor Functions Classes may be missing but JavaScript does support special constructor functions. By prefixing a call to a constructor function with the ‘new’ keyword we can tell the JavaScript runtime that we want the function to behave like a constructor and instantiate a new object containing the members defined by that function. Within a constructor function the ‘this’ keyword references the new object being created -  so a basic constructor function might be: function Person(name, age) { this.name = name; this.age = age; this.toString = function() { return this.name + " is " + age + " years old."; }; } var john = new Person("John Galt", 50); console.log(john.toString()); Note that by convention the name of a constructor function is always written in Pascal Case (the first letter of each word is capital). This is to distinguish between constructor functions and other functions. It is important that constructor functions be called with the ‘new’ keyword and that not constructor functions are not. There are two problems with the pattern constructor function pattern shown above: It makes inheritance difficult The toString() function is redefined for each new object created by the Person constructor. This is sub-optimal because the function should be shared between all of the instances of the Person type. Constructor Functions with a Prototype JavaScript functions have a special property called prototype. When an object is created by calling a JavaScript constructor all of the properties of the constructor’s prototype become available to the new object. In this way many Person objects can be created that can access the same prototype. An improved version of the above example can be written: function Person(name, age) { this.name = name; this.age = age; } Person.prototype = { toString: function() { return this.name + " is " + this.age + " years old."; } }; var john = new Person("John Galt", 50); console.log(john.toString()); In this version a single instance of the toString() function will now be shared between all Person objects. Private Members The short version is: there aren’t any. If a variable is defined, with the var keyword, within the constructor function then its scope is that function. Other functions defined within the constructor function will be able to access the private variable, but anything defined outside the constructor (such as functions on the prototype property) won’t have access to the private variable. Any variables defined on the constructor are automatically public. Some people solve this problem by prefixing properties with an underscore and then not calling those properties by convention. function Person(name, age) { this.name = name; this.age = age; } Person.prototype = { _getName: function() { return this.name; }, toString: function() { return this._getName() + " is " + this.age + " years old."; } }; var john = new Person("John Galt", 50); console.log(john.toString()); Note that the _getName() function is only private by convention – it is in fact a public function. Functional Object Construction Because of the weirdness involved in using constructor functions some JavaScript developers prefer to eschew them completely. They theorize that it is better to work with JavaScript’s functional nature than to try and force it to behave like a traditional class-oriented language. When using the functional approach objects are created by returning them from a factory function. An excellent side effect of this pattern is that variables defined with the factory function are accessible to the new object (due to closure) but are inaccessible from anywhere else. The Person example implemented using the functional object construction pattern is: var personFactory = function(name, age) { var privateVar = 7; return { toString: function() { return name + " is " + age * privateVar / privateVar + " years old."; } }; }; var john2 = personFactory("John Lennon", 40); console.log(john2.toString()); Note that the ‘new’ keyword is not used for this pattern, and that the toString() function has access to the name, age and privateVar variables because of closure. This pattern can be extended to provide inheritance and, unlike the constructor function pattern, it supports private variables. However, when working with JavaScript code bases you will find that the constructor function is more common – probably because it is a better approximation of mainstream class oriented languages like C# and Java. Inheritance Both of the above patterns can support inheritance but for now, favour composition over inheritance. Summary When JavaScript code exceeds simple browser automation object orientation can provide a powerful paradigm for controlling complexity. Both of the patterns presented in this article work – the choice is a matter of style. Only one question still remains; who is John Galt?

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• JavaScript Class Patterns

  - by Liam McLennan

  To write object-oriented programs we need objects, and likely lots of them. JavaScript makes it easy to create objects: var liam = { name: "Liam", age: Number.MAX_VALUE }; But JavaScript does not provide an easy way to create similar objects. Most object-oriented languages include the idea of a class, which is a template for creating objects of the same type. From one class many similar objects can be instantiated. Many patterns have been proposed to address the absence of a class concept in JavaScript. This post will compare and contrast the most significant of them. Simple Constructor Functions Classes may be missing but JavaScript does support special constructor functions. By prefixing a call to a constructor function with the ‘new’ keyword we can tell the JavaScript runtime that we want the function to behave like a constructor and instantiate a new object containing the members defined by that function. Within a constructor function the ‘this’ keyword references the new object being created -  so a basic constructor function might be: function Person(name, age) { this.name = name; this.age = age; this.toString = function() { return this.name + " is " + age + " years old."; }; } var john = new Person("John Galt", 50); console.log(john.toString()); Note that by convention the name of a constructor function is always written in Pascal Case (the first letter of each word is capital). This is to distinguish between constructor functions and other functions. It is important that constructor functions be called with the ‘new’ keyword and that not constructor functions are not. There are two problems with the pattern constructor function pattern shown above: It makes inheritance difficult The toString() function is redefined for each new object created by the Person constructor. This is sub-optimal because the function should be shared between all of the instances of the Person type. Constructor Functions with a Prototype JavaScript functions have a special property called prototype. When an object is created by calling a JavaScript constructor all of the properties of the constructor’s prototype become available to the new object. In this way many Person objects can be created that can access the same prototype. An improved version of the above example can be written: function Person(name, age) { this.name = name; this.age = age; } Person.prototype = { toString: function() { return this.name + " is " + this.age + " years old."; } }; var john = new Person("John Galt", 50); console.log(john.toString()); In this version a single instance of the toString() function will now be shared between all Person objects. Private Members The short version is: there aren’t any. If a variable is defined, with the var keyword, within the constructor function then its scope is that function. Other functions defined within the constructor function will be able to access the private variable, but anything defined outside the constructor (such as functions on the prototype property) won’t have access to the private variable. Any variables defined on the constructor are automatically public. Some people solve this problem by prefixing properties with an underscore and then not calling those properties by convention. function Person(name, age) { this.name = name; this.age = age; } Person.prototype = { _getName: function() { return this.name; }, toString: function() { return this._getName() + " is " + this.age + " years old."; } }; var john = new Person("John Galt", 50); console.log(john.toString()); Note that the _getName() function is only private by convention – it is in fact a public function. Functional Object Construction Because of the weirdness involved in using constructor functions some JavaScript developers prefer to eschew them completely. They theorize that it is better to work with JavaScript’s functional nature than to try and force it to behave like a traditional class-oriented language. When using the functional approach objects are created by returning them from a factory function. An excellent side effect of this pattern is that variables defined with the factory function are accessible to the new object (due to closure) but are inaccessible from anywhere else. The Person example implemented using the functional object construction pattern is: var john = new Person("John Galt", 50); console.log(john.toString()); var personFactory = function(name, age) { var privateVar = 7; return { toString: function() { return name + " is " + age * privateVar / privateVar + " years old."; } }; }; var john2 = personFactory("John Lennon", 40); console.log(john2.toString()); Note that the ‘new’ keyword is not used for this pattern, and that the toString() function has access to the name, age and privateVar variables because of closure. This pattern can be extended to provide inheritance and, unlike the constructor function pattern, it supports private variables. However, when working with JavaScript code bases you will find that the constructor function is more common – probably because it is a better approximation of mainstream class oriented languages like C# and Java. Inheritance Both of the above patterns can support inheritance but for now, favour composition over inheritance. Summary When JavaScript code exceeds simple browser automation object orientation can provide a powerful paradigm for controlling complexity. Both of the patterns presented in this article work – the choice is a matter of style. Only one question still remains; who is John Galt?

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• Passing the CAML thru the EY of the NEEDL

  - by PointsToShare

  © 2011 By: Dov Trietsch. All rights reserved Passing the CAML thru the EY of the NEEDL Definitions: CAML (Collaborative Application Markup Language) is an XML based markup language used in Microsoft SharePoint technologies  Anonymous: A camel is a horse designed by committee  Dov Trietsch: A CAML is a HORS designed by Microsoft  I was advised against putting any Camel and Sphinx rhymes in here. Look it up in Google!  _____ Now that we have dispensed with the dromedary jokes (BTW, I have many more, but they are not fit to print!), here is an interesting problem and its solution.  We have built a list where the title must be kept unique so I needed to verify the existence (or absence) of a list item with a particular title. Two methods came to mind:  1: Span the list until the title is found (result = found) or until the list ends (result = not found). This is an algorithm of complexity O(N) and for long lists it is a performance sucker. 2: Use a CAML query instead. Here, for short list we’ll encounter some overhead, but because the query results in an SQL query on the content database, it is of complexity O(LogN), which is significantly better and scales perfectly. Obviously I decided to go with the latter and this is where the CAML s--t hit the fan.   A CAML query returns a SPListItemCollection and I simply checked its Count. If it was 0, the item did not already exist and it was safe to add a new item with the given title. Otherwise I cancelled the operation and warned the user. The trouble was that I always got a positive. Most of the time a false positive. The count was greater than 0 regardles of the title I checked (except when the list was empty, which happens only once). This was very disturbing indeed. To solve my immediate problem which was speedy delivery, I reverted to the “Span the list” approach, but the problem bugged me, so I wrote a little console app by which I tested and tweaked and tested, time and again, until I found the solution. Yes, one can pass the proverbial CAML thru the ey of the needle (e’s missing on purpose).  So here are my conclusions:  CAML that does not work:  Note: QT is my quote:  char QT = Convert.ToChar((int)34); string titleQuery = "<Query>><Where><Eq>"; titleQuery += "<FieldRef Name=" + QT + "Title" + QT + "/>"; titleQuery += "<Value Type=" + QT + "Text" + QT + ">" + uniqueID + "</Value></Eq></Where></Query>"; titleQuery += "<ViewFields><FieldRef Name=" + QT + "Title" + QT + "/></ViewFields>";  Why? Even though U2U generates it, the <Query> and </Query> tags do not belong in the query that you pass. Start your query with the <Where> clause.  Also the <ViewFiels> clause does not belong. I used this clause to limit the returned collection to a single column, and I still wish to do it. I’ll show how this is done a bit later.   When you use the <Query> </Query> tags in you query, it’s as if you did not specify the query at all. What you get is the all inclusive default query for the list. It returns evey column and every item. It is expensive for both server and network because it does all the extra processing and eats plenty of bandwidth.   Now, here is the CAML that works  string titleQuery = "<Where><Eq>"; titleQuery += "<FieldRef Name=" + QT + "Title" + QT + "/>"; titleQuery += "<Value Type=" + QT + "Text" + QT + ">" + uniqueID + "</Value></Eq></Where>";  You’ll also notice that inside the unusable <ViewFields> clause above, we have a <FieldRef> clause. This is what we pass to the SPQuery object. Here is how:  SPQuery query = new SPQuery(); query.Query = titleQuery; query.ViewFields = "<FieldRef Name=" + QT + "Title" + QT + "/>"; query.RowLimit = 1; SPListItemCollection col = masterList.GetItems(query);  Two thing to note: we enter the view fields into the SPQuery object and we also limited the number of rows that the query returns. The latter is not always done, but in an existence test, there is no point in returning hundreds of rows. The query will now return one item or none, which is all we need in order to verify the existence (or non-existence) of items. Limiting the number of columns and the number of rows is a great performance enhancer. That’s all folks!!

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• Windows Workflow Foundation (WF) and things I wish were more intuitive

  - by pjohnson

  I've started using Windows Workflow Foundation, and so far ran into a few things that aren't incredibly obvious. Microsoft did a good job of providing a ton of samples, which is handy because you need them to get anywhere with WF. The docs are thin, so I've been bouncing between samples and downloadable labs to figure out how to implement various activities in a workflow. Code separation or not? You can create a workflow and activity in Visual Studio with or without code separation, i.e. just a .cs "Component" style object with a Designer.cs file, or a .xoml XML markup file with code behind (beside?) it. Absence any obvious advantage to one or the other, I used code separation for workflows and any complex custom activities, and without code separation for custom activities that just inherit from the Activity class and thus don't have anything special in the designer. So far, so good. Workflow Activity Library project type - What's the point of this separate project type? So far I don't see much advantage to keeping your custom activities in a separate project. I prefer to have as few projects as needed (and no fewer). The Designer's Toolbox window seems to find your custom activities just fine no matter where they are, and the debugging experience doesn't seem to be any different. Designer Properties - This is about the designer, and not specific to WF, but nevertheless something that's hindered me a lot more in WF than in Windows Forms or elsewhere. The Properties window does a good job of showing you property values when you hover the mouse over the values. But they don't do the same to find out what a control's type is. So maybe if I named all my activities "x1" and "x2" instead of helpful self-documenting names like "listenForStatusUpdate", then I could easily see enough of the type to determine what it is, but any names longer than those and all I get of the type is "System.Workflow.Act" or "System.Workflow.Compone". Even hitting the dropdown doesn't expand any wider, like the debugger quick watch "smart tag" popups do when you scroll through members. The only way I've found around this in VS 2008 is to widen the Properties dialog, losing precious designer real estate, then shrink it back down when you're done to see what you were doing. Really? WF Designer - This is about the designer, and I believe is specific to WF. I should be able to edit the XML in a .xoml file, or drag and drop using the designer. With WPF (at least in VS 2010 Ultimate), these are side by side, and changes to one instantly update the other. With WF, I have to right-click on the .xoml file, choose Open With, and pick XML Editor to edit the text. It looks like this is one way where WF didn't get the same attention WPF got during .NET Fx 3.0 development. Service - In the WF world, this is simply a class that talks to the workflow about things outside the workflow, not to be confused with how the term "service" is used in every other context I've seen in the Windows and .NET world, i.e. an executable that waits for events or requests from a client and services them (Windows service, web service, WCF service, etc.). ListenActivity - Such a great concept, yet so unintuitive. It seems you need at least two branches (EventDrivenActivity instances), one for your positive condition and one for a timeout. The positive condition has a HandleExternalEventActivity, and the timeout has a DelayActivity followed by however you want to handle the delay, e.g. a ThrowActivity. The timeout is simple enough; wiring up the HandleExternalEventActivity is where things get fun. You need to create a service (see above), and an interface for that service (this seems more complex than should be necessary--why not have activities just wire to a service directly?). And you need to create a custom EventArgs class that inherits from ExternalDataEventArgs--you can't create an ExternalDataEventArgs event handler directly, even if you don't need to add any more information to the event args, despite ExternalDataEventArgs not being marked as an abstract class, nor a compiler error nor warning nor any other indication that you're doing something wrong, until you run it and find that it always times out and get to check every place mentioned here to see why. Your interface and service need an event that consumes your custom EventArgs class, and a method to fire that event. You need to call that method from somewhere. Then you get to hope that you did everything just right, or that you can step through code in the debugger before your Delay timeout expires. Yes, it's as much fun as it sounds. TransactionScopeActivity - I had the bright idea of putting one in as a placeholder, then filling in the database updates later. That caused this error: The workflow hosting environment does not have a persistence service as required by an operation on the workflow instance "[GUID]". ...which is about as helpful as "Object reference not set to an instance of an object" and even more fun to debug. Google led me to this Microsoft Forums hit, and from there I figured out it didn't like that the activity had no children. Again, a Validator on TransactionScopeActivity would have pointed this out to me at design time, rather than handing me a nearly useless error at runtime. Easily enough, I disabled the activity and that fixed it. I still see huge potential in my work where WF could make things easier and more flexible, but there are some seriously rough edges at the moment. Maybe I'm just spoiled by how much easier and more intuitive development elsewhere in the .NET Framework is.

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• Wildcards!

  - by Tim Dexter

  Yes, its been a while, Im sorry, mumble, mumble ... no excuses. Well other than its been, as my son would say 'hecka busy.' On a brighter note I see Kan has been posting some cool stuff in my absence, long may he continue! I received a question today asking about using a wildcard in a template, something like: <?if:INVOICE = 'MLP*'?> where * is the wildcard Well that particular try does not work but you can do it without building your own wildcard function. XSL, the underpinning language of the RTF templates, has some useful string functions - you can find them listed here. I used the starts-with function to achieve a simple wildcard scenario but the contains can be used in conjunction with some of the others to build something more sophisticated. Assume I have a a list of friends and the amounts of money they owe me ... Im very generous and my interest rates a pretty competitive :0) <ROWSET> <ROW> <NAME>Andy</NAME> <AMT>100</AMT> </ROW> <ROW> <NAME>Andrew</NAME> <AMT>60</AMT> </ROW> <ROW> <NAME>Aaron</NAME> <AMT>50</AMT> </ROW> <ROW> <NAME>Alice</NAME> <AMT>40</AMT> </ROW> <ROW> <NAME>Bob</NAME> <AMT>10</AMT> </ROW> <ROW> <NAME>Bill</NAME> <AMT>100</AMT> </ROW> Now, listing my friends is easy enough <for-each:ROW> <NAME> <AMT> <end for-each> but lets say I just want to see all my friends beginning with 'A'. To do that I can use an XPATH expression to filter the data and tack it on to the for-each expression. This is more efficient that using an 'if' statement just inside the for-each. <?for-each:ROW[starts-with(NAME,'A')]?> will find me all the A's. The square braces denote the start of the XPATH expression. starts-with is the function Im calling and Im passing the value I want to check i.e. NAME and the string Im looking for. Just substitute in the characters you are looking for. You can of course use the function in a if statement too. <?if:starts-with(NAME,'A')?><?attribute@incontext:color;'red'?><?end if?> Notice I removed the square braces, this will highlight text red if the name begins with an 'A' You can even use the function to do conditional calculations: <?sum (AMT[starts-with(../NAME,'A')])?> Sum only the amounts where the name begins with an 'A' Notice the square braces are back, its a function we want to apply to the AMT field. Also notice that we need to use ../NAME. The AMT and NAME elements are at the same level in the tree, so when we are at the AMT level we need the ../ to go up a level to then come back down to test the NAME value. I have built out the above functions in a sample template here. Huge prizes for the first person to come up with a 'true' wildcard solution i.e. if NAME like '*im*exter* demand cash now!

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• Organization &amp; Architecture UNISA Studies &ndash; Chap 5

  - by MarkPearl

  Learning Outcomes Describe the operation of a memory cell Explain the difference between DRAM and SRAM Discuss the different types of ROM Explain the concepts of a hard failure and a soft error respectively Describe SDRAM organization Semiconductor Main Memory The two traditional forms of RAM used in computers are DRAM and SRAM DRAM (Dynamic RAM) Divided into two technologies… Dynamic Static Dynamic RAM is made with cells that store data as charge on capacitors. The presence or absence of charge in a capacitor is interpreted as a binary 1 or 0. Because capacitors have natural tendency to discharge, dynamic RAM requires periodic charge refreshing to maintain data storage. The term dynamic refers to the tendency of the stored charge to leak away, even with power continuously applied. Although the DRAM cell is used to store a single bit (0 or 1), it is essentially an analogue device. The capacitor can store any charge value within a range, a threshold value determines whether the charge is interpreted as a 1 or 0. SRAM (Static RAM) SRAM is a digital device that uses the same logic elements used in the processor. In SRAM, binary values are stored using traditional flip flop logic configurations. SRAM will hold its data as along as power is supplied to it. Unlike DRAM, no refresh is required to retain data. SRAM vs. DRAM DRAM is simpler and smaller than SRAM. Thus it is more dense and less expensive than SRAM. The cost of the refreshing circuitry for DRAM needs to be considered, but if the machine requires a large amount of memory, DRAM turns out to be cheaper than SRAM. SRAMS are somewhat faster than DRAM, thus SRAM is generally used for cache memory and DRAM is used for main memory. Types of ROM Read Only Memory (ROM) contains a permanent pattern of data that cannot be changed. ROM is non volatile meaning no power source is required to maintain the bit values in memory. While it is possible to read a ROM, it is not possible to write new data into it. An important application of ROM is microprogramming, other applications include library subroutines for frequently wanted functions, System programs, Function tables. A ROM is created like any other integrated circuit chip, with the data actually wired into the chip as part of the fabrication process. To reduce costs of fabrication, we have PROMS. PROMS are… Written only once Non-volatile Written after fabrication Another variation of ROM is the read-mostly memory, which is useful for applications in which read operations are far more frequent than write operations, but for which non volatile storage is required. There are three common forms of read-mostly memory, namely… EPROM EEPROM Flash memory Error Correction Semiconductor memory is subject to errors, which can be classed into two categories… Hard failure – Permanent physical defect so that the memory cell or cells cannot reliably store data Soft failure – Random error that alters the contents of one or more memory cells without damaging the memory (common cause includes power supply issues, etc.) Most modern main memory systems include logic for both detecting and correcting errors. Error detection works as follows… When data is to be read into memory, a calculation is performed on the data to produce a code Both the code and the data are stored When the previously stored word is read out, the code is used to detect and possibly correct errors The error checking provides one of 3 possible results… No errors are detected – the fetched data bits are sent out An error is detected, and it is possible to correct the error. The data bits plus error correction bits are fed into a corrector, which produces a corrected set of bits to be sent out An error is detected, but it is not possible to correct it. This condition is reported Hamming Code See wiki for detailed explanation. We will probably need to know how to do a hemming code – refer to the textbook (pg. 188 – 189) Advanced DRAM organization One of the most critical system bottlenecks when using high-performance processors is the interface to main memory. This interface is the most important pathway in the entire computer system. The basic building block of main memory remains the DRAM chip. In recent years a number of enhancements to the basic DRAM architecture have been explored, and some of these are now on the market including… SDRAM (Synchronous DRAM) DDR-DRAM RDRAM SDRAM (Synchronous DRAM) SDRAM exchanges data with the processor synchronized to an external clock signal and running at the full speed of the processor/memory bus without imposing wait states. SDRAM employs a burst mode to eliminate the address setup time and row and column line precharge time after the first access In burst mode a series of data bits can be clocked out rapidly after the first bit has been accessed SDRAM has a multiple bank internal architecture that improves opportunities for on chip parallelism SDRAM performs best when it is transferring large blocks of data serially There is now an enhanced version of SDRAM known as double data rate SDRAM or DDR-SDRAM that overcomes the once-per-cycle limitation of SDRAM

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• To Bit or Not To Bit

  - by Johnm

  'Twas a long day of troubleshooting and firefighting and now, with most of the office vacant, you face a blank scripting window to create a new table in his database. Many questions circle your mind like dirty water gurgling down the bathtub drain: "How normalized should this table be?", "Should I use an identity column?", "NVarchar or Varchar?", "Should this column be NULLABLE?", "I wonder what apple blue cheese bacon cheesecake tastes like?" Well, there are times when the mind goes it's own direction. A Bit About Bit At some point during your table creation efforts you will encounter the decision of whether to use the bit data type for a column. The bit data type is an integer data type that recognizes only the values of 1, 0 and NULL as valid. This data type is often utilized to store yes/no or true/false values. An example of its use would be a column called [IsGasoline] which would be intended to contain the value of 1 if the row's subject (a car) had a gasoline engine and a 0 if the subject did not have a gasoline engine. The bit data type can even be found in some of the system tables of SQL Server. For example, the sysssispackages table in the msdb database which contains SQL Server Integration Services Package information for the packages stored in SQL Server. This table contains a column called [IsEncrypted]. A value of 1 indicates that the package has been encrypted while the value of 0 indicates that it is not. I have learned that the most effective way to disperse the crowd that surrounds the office coffee machine is to engage into SQL Server debates. The bit data type has been one of the most reoccurring, as well as the most enjoyable, of these topics. It contains a practical side and a philosophical side. Practical Consideration This data type certainly has its place and is a valuable option for database design; but it is often used in situations where the answer is really not a pure true/false response. In addition, true/false values are not very informative or scalable. Let's use the previously noted [IsGasoline] column for illustration. While on the surface it appears to be a rather simple question when evaluating a car: "Does the car have a gasoline engine?" If the person entering data is entering a row for a Jeep Liberty, the response would be a 1 since it has a gasoline engine. If the person is entering data is entering a row for a Chevrolet Volt, the response would be a 0 since it is an electric engine. What happens when a person is entering a row for the gasoline/electric hybrid Toyota Prius? Would one person's conclusion be consistent with another person's conclusion? The argument could be made that the current intent for the database is to be used only for pure gasoline and pure electric engines; but this is where the scalability issue comes into play. With the use of a bit data type a database modification and data conversion would be required if the business decided to take on hybrid engines. Whereas, alternatively, if the int data type were used as a foreign key to a reference table containing the engine type options, the change to include the hybrid option would only require an entry into the reference table. Philosophical Consideration Since the bit data type is often used for true/false or yes/no data (also called Boolean) it presents a philosophical conundrum of what to do about the allowance of the NULL value. The inclusion of NULL in a true/false or yes/no response simply violates the logical principle of bivalence which states that "every proposition is either true or false". If NULL is not true, then it must be false. The mathematical laws of Boolean logic support this concept by stating that the only valid values of this scenario are 1 and 0. There is another way to look at this conundrum: NULL is also considered to be the absence of a response. In other words, it is the equivalent to "undecided". Anyone who watches the news can tell you that polls always include an "undecided" option. This could be considered a valid option in the world of yes/no/dunno. Through out all of these considerations I have discovered one absolute certainty: When you have found a person, or group of persons, who are willing to entertain a philosophical debate of the bit data type, you have found some true friends.

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• TFS API Add Favorites programmatically

  - by Tarun Arora

  01 – What are we trying to achieve? In this blog post I’ll be showing you how to add work item queries as favorites, it is also possible to use the same technique to add build definition as favorites. Once a shared query or build definition has been added as favorite it will show up on the team web access.  In this blog post I’ll be showing you a work around in the absence of a proper API how you can add queries to team favorites. 02 – Disclaimer There is no official API for adding favorites programmatically. In the work around below I am using the Identity service to store this data in a property bag which is used during display of favorites on the team web site. This uses an internal data structure that could change over time, there is no guarantee about the key names or content of the values. What is shown below is a workaround for a missing API. 03 – Concept There is no direct API support for favorites, but you could work around it using the identity service in TFS.  Favorites are stored in the property bag associated with the TeamFoundationIdentity (either the ‘team’ identity or the users identity depending on if these are ‘team’ or ‘my’ favorites).  The data is stored as json in the property bag of the identity, the key being prefixed by ‘Microsoft.TeamFoundation.Framework.Server.IdentityFavorites’. References - Microsoft.TeamFoundation.WorkItemTracking.Client - using Microsoft.TeamFoundation.Client; - using Microsoft.TeamFoundation.Framework.Client; - using Microsoft.TeamFoundation.Framework.Common; - using Microsoft.TeamFoundation.ProcessConfiguration.Client; - using Microsoft.TeamFoundation.Server; - using Microsoft.TeamFoundation.WorkItemTracking.Client; Services - IIdentityManagementService2 - TfsTeamService - WorkItemStore 04 – Solution Lets start by connecting to TFS programmatically // Create an instance of the services to be used during the program private static TfsTeamProjectCollection _tfs; private static ProjectInfo _selectedTeamProject; private static WorkItemStore _wis; private static TfsTeamService _tts; private static TeamSettingsConfigurationService _teamConfig; private static IIdentityManagementService2 _ids; // Connect to TFS programmatically public static bool ConnectToTfs() { var isSelected = false; var tfsPp = new TeamProjectPicker(TeamProjectPickerMode.SingleProject, false); tfsPp.ShowDialog(); _tfs = tfsPp.SelectedTeamProjectCollection; if (tfsPp.SelectedProjects.Any()) { _selectedTeamProject = tfsPp.SelectedProjects[0]; isSelected = true; } return isSelected; } Lets get all the work item queries from the selected team project static readonly Dictionary<string, string> QueryAndGuid = new Dictionary<string, string>(); // Get all queries and query guid in the selected team project private static void GetQueryGuidList(IEnumerable<QueryItem> query) { foreach (QueryItem subQuery in query) { if (subQuery.GetType() == typeof(QueryFolder)) GetQueryGuidList((QueryFolder)subQuery); else { QueryAndGuid.Add(subQuery.Name, subQuery.Id.ToString()); } } }   Pass the name of a valid Team in your team project and a name of a valid query in your team project. The team details will be extracted using the team name and query GUID will be extracted using the query name. These details will be used to construct the key and value that will be passed to the SetProperty method in the Identity service.           Key           “Microsoft.TeamFoundation.Framework.Server.IdentityFavorites..<TeamProjectURI>.<TeamId>.WorkItemTracking.Queries.<newGuid1>”           Value           "{"data":"<QueryGuid>","id":"<NewGuid1>","name":"<QueryKey>","type":"Microsoft.TeamFoundation.WorkItemTracking.QueryItem”}"           // Configure a Work Item Query for the given team private static void ConfigureTeamFavorites(string teamName, string queryName) { _ids = _tfs.GetService<IIdentityManagementService2>(); var g = Guid.NewGuid(); var guid = string.Empty; var teamDetail = _tts.QueryTeams(_selectedTeamProject.Uri).FirstOrDefault(t => t.Name == teamName); foreach (var q in QueryAndGuid.Where(q => q.Key == queryName)) { guid = q.Value; } if(guid == string.Empty) { Console.WriteLine("Query '{0}' - Not found!", queryName); return; } var key = string.Format( "Microsoft.TeamFoundation.Framework.Server.IdentityFavorites..{0}.{1}.WorkItemTracking.Queries{2}", new Uri(_selectedTeamProject.Uri).Segments.LastOrDefault(), teamDetail.Identity.TeamFoundationId, g); var value = string.Format( @"{0}""data"":""{1}"",""id"":""{2}"",""name"":""{3}"",""type"":""Microsoft.TeamFoundation.WorkItemTracking.QueryItem""{4}", "{", guid, g, QueryAndGuid.FirstOrDefault(q => q.Value==guid).Key, "}"); teamDetail.Identity.SetProperty(IdentityPropertyScope.Local, key, value); _ids.UpdateExtendedProperties(teamDetail.Identity); Console.WriteLine("{0}Added Query '{1}' as Favorite", Environment.NewLine, queryName); }   If you have any questions or suggestions leave a comment. Enjoy!

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• Agile Testing Days 2012 – My First Conference!

  - by Chris George

  I’d like to give you a bit of background first… so please bear with me! In 1996, whilst studying for my final year of my degree, I applied for a job as a C++ Developer at a small software house in Hertfordshire  After bodging up the technical part of the interview I didn’t get the job, but was offered a position as a QA Engineer instead. The role sounded intriguing and the pay was pretty good so in the absence of anything else I took it. Here began my career in the world of software testing! Back then, testing/QA was often an afterthought, something that was bolted on to the development process and very much a second class citizen. Test automation was rare, and tools were basic or non-existent! The internet was just starting to take off, and whilst there might have been testing communities and resources, we were certainly not exposed to any of them. After 8 years I moved to another small company, and again didn’t find myself exposed to any of the changes that were happening in the industry. It wasn’t until I joined Red Gate in 2008 that my view of testing and software development as a whole started to expand. But it took a further 4 years for my view of testing to be totally blown open, and so the story really begins… In May 2012 I was fortunate to land the role of Head of Test Engineering. Soon after, I received an email with details for the “Agile Testi However, in my new role, I decided that it was time to bite the bullet and at least go to one conference. Perhaps I could get some new ideas to supplement and support some of the ideas I already had.ng Days” conference in Potsdam, Germany. I looked over the suggested programme and some of the talks peeked my interest. For numerous reasons I’d shied away from attending conferences in the past, one of the main ones being that I didn’t see much benefit in attending loads of talks when I could just read about stuff like that on the internet. So, on the 18th November 2012, myself and three other Red Gaters boarded a plane at Heathrow bound for Potsdam, Germany to attend Agile Testing Days 2012. Tutorial Day – “Software Testing Reloaded” We chose to do the tutorials on the 19th, I chose the one titled “Software Testing Reloaded – So you wanna actually DO something? We’ve got just the workshop for you. Now with even less powerpoint!”. With such a concise and serious title I just had to see what it was about! I nervously entered the room to be greeted by tables, chairs etc all over the place, not set out and frankly in one hell of a mess! There were a few people in there playing a game with dice. Okaaaay… this is going to be a long day! Actually the dice game was an exercise in deduction and simplification… I found it very interesting and is certainly something I’ll be using at work as a training exercise! (I won’t explain the game here cause I don’t want to let the cat out of the bag…) The tutorial consisted of several games, exploring different aspects of testing. They were all practical yet required a fair amount of thin king. Matt Heusser and Pete Walen were running the tutorial, and presented it in a very relaxed and light-hearted manner. It was really my first experience of working in small teams with testers from very different backgrounds, and it was really enjoyable. Matt & Pete were very approachable and offered advice where required whilst still making you work for the answers! One of the tasks was to devise several strategies for testing some electronic dice. The premise was that a Vegas casino wanted to use the dice to appeal to the twenty-somethings interested in tech, but needed assurance that they were as reliable and random as traditional dice. This was a very interesting and challenging exercise that forced us to challenge various assumptions, determine/clarify requirements but most of all it was frustrating because the dice made a very very irritating beeping noise. Multiple that by at least 12 dice and I was dreaming about them all that night!! Some of the main takeaways that were brilliantly demonstrated through the games were not to make assumptions, challenge requirements, and have fun testing! The tutorial lasted the whole day, but to be honest the day went very quickly! My introduction into the conference experience started very well indeed, and I would talk to both Matt and Pete several times during the 4 days. Days 1,2 & 3 will be coming soon…  

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• Remote Workers...We're Not That Bad!

  - by user12601034

  I work from home a lot – my team is located in different cities and countries, my manager is in a different city, and most of our work is done via conference calls, email and collaboration through Oracle Social Network. We’ve figured out how to be effective and involve team members, regardless of where we are all located. When I mention that I work from home, a lot of my friends will laugh, roll their eyes or use their fingers to make quotation marks around “work from home.” Their belief is that I’m sitting at home, eating bon-bons and watching television. The attempts at humor only multiply when they know that my husband also mostly works from home. So, it was with great joy that I read the Lifehacker article Why Remote Workers Are More (Yes, More) Engaged. I’m not going to re-write the article for you, but four highlights from the article include: Proximity breeds complacency –because communicating with employees sitting next to you is so easy, you may not do it well. Absence makes people try harder to connect – because you have to make an effort to connect to your team, you tend to pay better attention when you do connect Leaders of virtual team make better use of tools – when working remotely, you will use technology (many different forms of it) to connect with your team. This daily use of the tools makes you more proficient with those tools Leaders of far-flung teams maximize the time spent together – getting together takes effort, time and money, so leaders tend to filter out distractions when teams do get together. These points made me happy because I’ve seen the same things play out in my team located around the world. And I’m not saying that a virtual team is more effective than a co-located team – but my virtual team doesn’t have the option of filing into a conference room for a face-to-face meeting whenever we want. Instead, we have to figure out how to work effectively without meeting face-to-face. Am I more engaged as a remote worker? I’d like to think that I am. I’ve been on calls with colleagues at 3am – this would never happen if my only option was to be in the office. I can leave my “office” to pick up my kids from school…and I’m willingly back online after kids are in bed to finish up anything I need to. Oracle Social Network lets me use my iPad to engage with my teammates when I’m waiting at music lessons, the doctor’s office or any place else with a network connection. I feel like I’m more connected with my team, and I feel like I’m more connected with my family life. So yes, I am a remote worker, and I am engaged. If you lead a virtual team, I challenge you to increase the ways that you communicate to effectively engage your team. If you are on a virtual team, I challenge you to think about how you might interact with team members to keep both them and yourself engaged in your work. And if you have some great ideas on how to make virtual teams (and workers) effective and engaged, please share those ideas in the comments! Now, if you’ll excuse me, I need to go get a bon-bon...   :) Normal 0 false false false EN-US X-NONE X-NONE /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin-top:0in; mso-para-margin-right:0in; mso-para-margin-bottom:10.0pt; mso-para-margin-left:0in; line-height:115%; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;}

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• OBIA on Teradata - Part 1 Loader and Monitoring

  - by Mohan Ramanuja

  Normal 0 false false false EN-US X-NONE X-NONE /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} The out-of-the-box (OOB) OBIA Informatica mappings come with TPump loader.   TPUMP  FASTLOAD TPump does not lock the table. FastLoad applies exclusive lock on the table. The table that TPump is loading can have data. The table that FastLoad is loading needs to be empty. Normal 0 false false false EN-US X-NONE X-NONE /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} TPump is not efficient with lookups. FastLoad is more efficient in the absence of lookups. Normal 0 false false false EN-US X-NONE X-NONE /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} The out-of the box Informatica mappings come with TPump loader. There is chance for bottleneck in writer thread The out-of the box tables in Teradata supplied with OBAW features all Dimension and Fact tables using ROW_WID as the key for primary index. Also, all staging tables use integration_id as the key for primary index. This reduces skewing of data across Teradata AMPs.You can use an SQL statement similar to the following to determine if data for a given table is distributed evenly across all AMP vprocs. The SQL statement displays the AMP with the most used through the AMP with the least-used space, investigating data distribution in the Message table in database RST.SELECT vproc,CurrentPermFROM DBC.TableSizeWHERE Databasename = ‘PRJ_CRM_STGC’AND Tablename = ‘w_party_per_d’ORDER BY 2 descIf you suspect distribution problems (skewing) among AMPS, the following is a sample of what you might enter for a three-column PI:SELECT HASHAMP (HASHBUCKET (HASHROW (col_x, col_y, col_z))), count (*)FROM hash15GROUP BY 1ORDER BY 2 desc; ETL Error Monitoring Error Table – These are tables that start with ET. Location and name can be specified in Informatica session as well as the loader connection.Loader Log – Loader log is available in the Informatica server under the session log folder. These give feedback on the loader parameters such as Packing Factor to use. These however need to be monitored in the production environment. The recommendations made in one environment may not be used in another environment.Log Table – These are tables that start with TL. These are sparse on information.Bad File – This is the Informatica file generated in case there is data quality issues

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• ASP.Net Web Farm Monitoring

  - by cisellis

  I am looking for suggestions on doing some simple monitoring of an ASP.Net web farm as close to real-time as possible. The objectives of this question are to: Identify the best way to monitor several Windows Server production boxes during short (minutes long) period of ridiculous load Receive near-real-time feedback on a few key metrics about each box. These are simple metrics available via WMI such as CPU, Memory and Disk Paging. I am defining my time constraints as soon as possible with 120 seconds delayed being the absolute upper limit. Monitor whether any given box is up (with "up" being defined as responding web requests in a reasonable amount of time) Here are more details, things I've tried, etc. I am not interested in logging. We have logging solutions in place. I have looked at solutions such as ELMAH which don't provide much in the way of hardware monitoring and are not visible across an entire web farm. ASP.Net Health Monitoring is too broad, focuses too much on logging and is not acceptable for deep analysis. We are on Amazon Web Services and we have looked into CloudWatch. It looks great but messages in the forum indicate that the metrics are often a few minutes behind, with one thread citing 2 minutes as the absolute soonest you could expect to receive the feedback. This would be good to have for later analysis but does not help us real-time Stuff like JetBrains profiler is good for testing but again, not helpful during real-time monitoring. The closest out-of-box solution I've seen is Nagios which is free and appears to measure key indicators on any kind of box, including Windows. However, it appears to require a Linux box to run itself on and a good deal of manual configuration. I'd prefer to not spend my time mining config files and then be up a creek when it fails in production since Linux is not my main (or even secondary) environment. Are there any out-of-box solutions that I am missing? Obviously a windows-based solution that is easy to setup is ideal. I don't require many bells and whistles. In the absence of an out-of-box solution, it seems easy for me to write something simple to handle what I need. I've been thinking a simple client-server setup where the server requests a few WMI metrics from each client over http and sticks them in a database. We could then monitor the metrics via a query or a dashboard or something. If the client doesn't respond, it's effectively down. Any problems with this, best practices, or other ideas? Thanks for any help/feedback.

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• Most efficient method to query a Young Tableau

  - by Matthieu M.

  A Young Tableau is a 2D matrix A of dimensions M*N such that: i,j in [0,M)x[0,N): for each p in (i,M), A[i,j] <= A[p,j] for each q in (j,N), A[i,j] <= A[i,q] That is, it's sorted row-wise and column-wise. Since it may contain less than M*N numbers, the bottom-right values might be represented either as missing or using (in algorithm theory) infinity to denote their absence. Now the (elementary) question: how to check if a given number is contained in the Young Tableau ? Well, it's trivial to produce an algorithm in O(M*N) time of course, but what's interesting is that it is very easy to provide an algorithm in O(M+N) time: Bottom-Left search: Let x be the number we look for, initialize i,j as M-1, 0 (bottom left corner) If x == A[i,j], return true If x < A[i,j], then if i is 0, return false else decrement i and go to 2. Else, if j is N-1, return false else increment j This algorithm does not make more than M+N moves. The correctness is left as an exercise. It is possible though to obtain a better asymptotic runtime. Pivot Search: Let x be the number we look for, initialize i,j as floor(M/2), floor(N/2) If x == A[i,j], return true If x < A[i,j], search (recursively) in A[0:i-1, 0:j-1], A[i:M-1, 0:j-1] and A[0:i-1, j:N-1] Else search (recursively) in A[i+1:M-1, 0:j], A[i+1:M-1, j+1:N-1] and A[0:i, j+1:N-1] This algorithm proceed by discarding one of the 4 quadrants at each iteration and running recursively on the 3 left (divide and conquer), the master theorem yields a complexity of O((N+M)**(log 3 / log 4)) which is better asymptotically. However, this is only a big-O estimation... So, here are the questions: Do you know (or can think of) an algorithm with a better asymptotical runtime ? Like introsort prove, sometimes it's worth switching algorithms depending on the input size or input topology... do you think it would be possible here ? For 2., I am notably thinking that for small size inputs, the bottom-left search should be faster because of its O(1) space requirement / lower constant term.

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• plane bombing problems- help

  - by peiska

  I'm training code problems, and on this one I am having problems to solve it, can you give me some tips how to solve it please. The problem is something like this: Your task is to find the sequence of points on the map that the bomber is expected to travel such that it hits all vital links. A link from A to B is vital when its absence isolates completely A from B. In other words, the only way to go from A to B (or vice versa) is via that link. Notice that if we destroy for example link (d,e), it becomes impossible to go from d to e,m,l or n in any way. A vital link can be hit at any point that lies in its segment (e.g. a hit close to d is as valid as a hit close to e). Of course, only one hit is enough to neutralize a vital link. Moreover, each bomb affects an exact circle of radius R, i.e., every segment that intersects that circle is considered hit. Due to enemy counter-attack, the plane may have to retreat at any moment, so the plane should follow, at each moment, to the closest vital link possible, even if in the end the total distance grows larger. Given all coordinates (the initial position of the plane and the nodes in the map) and the range R, you have to determine the sequence of positions in which the plane has to drop bombs. This sequence should start (takeoff) and finish (landing) at the initial position. Except for the start and finish, all the other positions have to fall exactly in a segment of the map (i.e. it should correspond to a point in a non-hit vital link segment). The coordinate system used will be UTM (Universal Transverse Mercator) northing and easting, which basically corresponds to a Euclidian perspective of the world (X=Easting; Y=Northing). Input Each input file will start with three floating point numbers indicating the X0 and Y0 coordinates of the airport and the range R. The second line contains an integer, N, indicating the number of nodes in the road network graph. Then, the next N (<10000) lines will each contain a pair of floating point numbers indicating the Xi and Yi coordinates (1 No two links will ever cross with each other. Output The program will print the sequence of coordinates (pairs of floating point numbers with exactly one decimal place), each one at a line, in the order that the plane should visit (starting and ending in the airport). Sample input 1 102.3 553.9 0.2 14 342.2 832.5 596.2 638.5 479.7 991.3 720.4 874.8 744.3 1284.1 1294.6 924.2 1467.5 659.6 1802.6 659.6 1686.2 860.7 1548.6 1111.2 1834.4 1054.8 564.4 1442.8 850.1 1460.5 1294.6 1485.1 17 1 2 1 3 2 4 3 4 4 5 4 6 6 7 7 8 8 9 8 10 9 10 10 11 6 11 5 12 5 13 12 13 13 14 Sample output 1 102.3 553.9 720.4 874.8 850.1 1460.5 102.3 553.9

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• Are there compelling reasons not to use Groovy?

  - by Leonard H Martin

  I'm developing a LoB application in Java after a long absence from the platform (having spent the last 8 years or so entrenched in Fortran, C, a smidgin of C++ and latterly .Net). Java, the language, is not much changed from how I remember it. I like it's strengths and I can work around its weaknesses - the platform has grown and deciding upon the myriad of different frameworks which appear to do much the same thing as one another is a different story; but that can wait for another day - all-in-all I'm comfortable with Java. However, over the last couple of weeks I've become enamoured with Groovy, and purely from a selfish point of view: but not just because it makes development against the JVM a more succinct and entertaining (and, well, "groovy") proposition than Java (the language). What strikes me most about Groovy is its inherent maintainability. We all (I hope!) strive to write well documented, easy to understand code. However, sometimes the languages we use themselves defeat us. An example: in 2001 I wrote a library in C to translate EDIFACT EDI messages into ANSI X12 messages. This is not a particularly complicated process, if slightly involved, and I thought at the time I had documented the code properly - and I probably had - but some six years later when I revisited the project (and after becoming acclimatised to C#) I found myself lost in so much C boilerplate (mallocs, pointers, etc. etc.) that it took three days of thoughtful analysis before I finally understood what I'd been doing six years previously. This evening I've written about 2000 lines of Java (it is the day of rest, after all!). I've documented as best as I know how, but, but, of those 2000 lines of Java a significant proportion is Java boiler plate. This is where I see Groovy and other dynamic languages winning through - maintainability and later comprehension. Groovy lets you concentrate on your intent without getting bogged down on the platform specific implementation; it's almost, but not quite, self documenting. I see this as being a huge boon to me when I revisit my current project (which I'll port to Groovy asap) in several years time and to my successors who will inherit it and carry on the good work. So, are there any reasons not to use Groovy?

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• Error on 64 Bit Install of IIS &ndash; LoadLibraryEx failed on aspnet_filter.dll

  - by Rick Strahl

  I’ve been having a few problems with my Windows 7 install and trying to get IIS applications to run properly in 64 bit. After installing IIS and creating virtual directories for several of my applications and firing them up I was left with the following error message from IIS: Calling LoadLibraryEx on ISAPI filter “c:\windows\Microsoft.NET\Framework\v4.0.30319\aspnet_filter.dll” failed This is on Windows 7 64 bit and running on an ASP.NET 4.0 Application configured for running 64 bit (32 bit disabled). It’s also on what is essentially a brand new installation of IIS and Windows 7. So it failed right out of the box. The problem here is that IIS is trying to loading this ISAPI filter from the 32 bit folder – it should be loading from Framework64 folder note the Framework folder. The aspnet_filter.dll component is a small Win32 ISAPI filter used to back up the cookieless session state for ASP.NET on IIS 7 applications. It’s not terribly important because of this focus, but it’s a default loaded component. After a lot of fiddling I ended up with two solutions (with the help and support of some Twitter folks): Switch IIS to run in 32 bit mode Fix the filter listing in ApplicationHost.config Switching IIS to allow 32 Bit Code This is a quick fix for the problem above which enables 32 bit code in the Application Pool. The problem above is that IIS is trying to load a 32 bit ISAPI filter and enabling 32 bit code gets you around this problem. To configure your Application Pool, open the Application Pool in IIS Manager bring up Advanced Options and Enable 32 Bit Applications: And voila the error message above goes away. Fix Filters Enabling 32 bit code is a quick fix solution to this problem, but not an ideal one. If you’re running a pure .NET application that doesn’t need to do COM or pInvoke Interop with 32 bit apps there’s usually no need for enabling 32 bit code in an Application Pool as you can run in native 64 bit code. So trying to get 64 bit working natively is a pretty key feature in my opinion :-) So what’s the problem – why is IIS trying to load a 32 bit DLL in a 64 bit install, especially if the application pool is configured to not allow 32 bit code at all? The problem lies in the server configuration and the fact that 32 bit and 64 bit configuration settings exist side by side in IIS. If I open my Default Web Site (or any other root Web Site) and go to the ISAPI filter list here’s what I see: Notice that there are 3 entries for ASP.NET 4.0 in this list. Only two of them however are specifically scoped to the specifically to 32 bit or 64 bit. As you can see the 64 bit filter correctly points at the Framework64 folder to load the dll, while both the 32 bit and the ‘generic’ entry point at the plain Framework 32 bit folder. Aha! Hence lies our problem. You can edit ApplicationHost.config manually, but I ran into the nasty issue of not being able to easily edit that file with the 32 bit editor (who ever thought that was a good idea???? WTF). You have to open ApplicationHost.Config in a 64 bit native text editor – which Visual Studio is not. Or my favorite editor: EditPad Pro. Since I don’t have a native 64 bit editor handy Notepad was my only choice. Or as an alternative you can use the IIS 7.5 Configuration Editor which lets you interactively browse and edit most ApplicationHost settings. You can drill into the configuration hierarchy visually to find your keys and edit attributes and sub values in property editor type interface. I had no idea this tool existed prior to today and it’s pretty cool as it gives you some visual clues to options available – especially in absence of an Intellisense scheme you’d get in Visual Studio (which doesn’t work). To use the Configuration Editor go the Web Site root and use the Configuration Editor option in the Management Group. Drill into System.webServer/isapiFilters and then click on the Collection’s … button on the right. You should now see a display like this: which shows all the same attributes you’d see in ApplicationHost.config (cool!). These entries correspond to these raw ApplicationHost.config entries: <filter name="ASP.Net_4.0" path="C:\Windows\Microsoft.NET\Framework\v4.0.30319\aspnet_filter.dll" enableCache="true" preCondition="runtimeVersionv4.0" /> <filter name="ASP.Net_4.0_64bit" path="C:\Windows\Microsoft.NET\Framework64\v4.0.30319\aspnet_filter.dll" enableCache="true" preCondition="runtimeVersionv4.0,bitness64" /> <filter name="ASP.Net_4.0_32bit" path="C:\Windows\Microsoft.NET\Framework\v4.0.30319\aspnet_filter.dll" enableCache="true" preCondition="runtimeVersionv4.0,bitness32" /> The key attribute we’re concerned with here is the preCondition and the bitness subvalue. Notice that the ‘generic’ version – which comes first in the filter list – has no bitness assigned to it, so it defaults to 32 bit and the 32 bit dll path. And this is where our problem comes from. The simple solution to fix the startup problem is to remove the generic entry from this list here or in the filters list shown earlier and leave only the bitness specific versions active. The preCondition attribute acts as a filter and as you can see here it filters the list by runtime version and bitness value. This is something to keep an eye out in general – if a bitness values are missing it’s easy to run into conflicts like this with any settings that are global and especially those that load modules and handlers and other executable code. On 64 bit systems it’s a good idea to explicitly set the bitness of all entries or remove the non-specific versions and add bit specific entries. So how did this get misconfigured? I installed IIS before everything else was installed on this machine and then went ahead and installed Visual Studio. I suspect the Visual Studio install munged this up as I never saw a similar problem on my live server where everything just worked right out of the box. In searching about this problem a lot of solutions pointed at using aspnet_regiis –r from the Framework64 directory, but that did not fix this extra entry in the filters list – it adds the required 32 bit and 64 bit entries, but it doesn’t remove the errand un-bitness set entry. Hopefully this post will help out anybody who runs into a similar situation without having to trouble shoot all the way down into the configuration settings and noticing the bitness settings. It’s a good lesson learned for me – this is my first desktop install of a 64 bit OS and things like this are what I was reluctant to find. Now that I ran into this I have a good idea what to look for with 32/64 bit misconfigurations in IIS at least.© Rick Strahl, West Wind Technologies, 2005-2011Posted in IIS7   ASP.NET  

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• So, how is the Oracle HCM Cloud User Experience? In a word, smokin’!

  - by Edith Mireles-Oracle

  By Misha Vaughan, Oracle Applications User Experience Oracle unveiled its game-changing cloud user experience strategy at Oracle OpenWorld 2013 (remember that?) with a new simplified user interface (UI) paradigm.  The Oracle HCM cloud user experience is about light-weight interaction, tailored to the task you are trying to accomplish, on the device you are comfortable working with. A key theme for the Oracle user experience is being able to move from smartphone to tablet to desktop, with all of your data in the cloud. The Oracle HCM Cloud user experience provides designs for better productivity, no matter when and how your employees need to work. Release 8  Oracle recently demonstrated how fast it is moving development forward for our cloud applications, with the availability of release 8.  In release 8, users will see expanded simplicity in the HCM cloud user experience, such as filling out a time card and succession planning. Oracle has also expanded its mobile capabilities with task flows for payslips, managing absences, and advanced analytics. In addition, users will see expanded extensibility with the new structures editor for simplified pages, and the with the user interface text editor, which allows you to update language throughout the UI from one place. If you don’t like calling people who work for you “employees,” you can use this tool to create a term that is suited to your business.  Take a look yourself at what’s available now. What are people saying?Debra Lilley (@debralilley), an Oracle ACE Director who has a long history with Oracle Applications, recently gave her perspective on release 8: “Having had the privilege of seeing a preview of release 8, I am again impressed with the enhancements around simplified UI. Even more so, at a user group event in London this week, an existing Cloud HCM customer speaking publically about his implementation said he was very excited about release 8 as the absence functionality was so superior and simple to use.”  In an interview with Lilley for a blog post by Dennis Howlett  (@dahowlett), we probably couldn’t have asked for a more even-handed look at the Oracle Applications Cloud and the impact of user experience. Take the time to watch all three videos and get the full picture.  In closing, Howlett’s said: “There is always the caveat that getting from the past to Fusion [from the editor: Fusion is now called the Oracle Applications Cloud] is not quite as simple as may be painted, but the outcomes are much better than anticipated in large measure because the user experience is so much better than what went before.” Herman Slange, Technical Manager with Oracle Applications partner Profource, agrees with that comment. “We use on-premise Financials & HCM for internal use. Having a simple user interface that works on a desktop as well as a tablet for (very) non-technical users is a big relief. Coming from E-Business Suite, there is less training (none) required to access HCM content.  From a technical point of view, having the abilities to tailor the simplified UI very easy makes it very efficient for us to adjust to specific customer needs.  When we have a conversation about simplified UI, we just hand over a tablet and ask the customer to just use it. No training and no explanation required.” Finally, in a story by Computer Weekly  about Oracle customer BG Group, a natural gas exploration and production company based in the UK and with a presence in 20 countries, the author states: “The new HR platform has proved to be easier and more intuitive for HR staff to use than the previous SAP-based technology.” What’s Next for Oracle’s Applications Cloud User Experiences? This is the question that Steve Miranda, Oracle Executive Vice President, Applications Development, asks the Applications User Experience team, and we’ve been hard at work for some time now on “what’s next.”  I can’t say too much about it, but I can tell you that we’ve started talking to customers and partners, under non-disclosure agreements, about user experience concepts that we are working on in order to get their feedback. We recently had a chance to talk about possibilities for the Oracle HCM Cloud user experience at an Oracle HCM Southern California Customer Success Summit. This was a fantastic event, hosted by Shane Bliss and Vance Morossi of the Oracle Client Success Team. We got to use the uber-slick facilities of Allergan, our hosts (of Botox fame), headquartered in Irvine, Calif., with a presence in more than 100 countries. Photo by Misha Vaughan, Oracle Applications User Experience Vance Morossi, left, and Shane Bliss, of the Oracle Client Success Team, at an Oracle HCM Southern California Customer Success Summit.  We were treated to a few really excellent talks around human resources (HR). Alice White, VP Human Resources, discussed Allergan's process for global talent acquisition -- how Allergan has designed and deployed a global process, and global tools, along with Oracle and Cognizant, and are now at the end of a global implementation. She shared a couple of insights about the journey for Allergan: “One of the major areas for improvement was on role clarification within the company.” She said the company is “empowering managers and deputizing them as recruiters. Now it is a global process that is nimble and efficient."  Deepak Rammohan, VP Product Management, HCM Cloud, Oracle, also took the stage to talk about pioneering modern HR. He reflected modern HR problems of getting the right data about the workforce, the importance of getting the right talent as a key strategic initiative, and other workforce insights. "How do we design systems to deal with all of this?” he asked. “Make sure the systems are talent-centric. The next piece is collaborative, engaging, and mobile. A lot of this is influenced by what users see today. The last thing is around insight; insight at the point of decision-making." Rammohan showed off some killer HCM Cloud talent demos focused on simplicity and mobility that his team has been cooking up, and closed with a great line about the nature of modern recruiting: "Recruiting is a team sport." Deepak Rammohan, left, and Jake Kuramoto, both of Oracle, debate the merits of a Google Glass concept demo for recruiters on-the-go. Later, in an expo-style format, the Apps UX team showed several concepts for next-generation HCM Cloud user experiences, including demos shown by Jake Kuramoto (@jkuramoto) of The AppsLab, and Aylin Uysal (@aylinuysal), Director, HCM Cloud user experience. We even hauled out our eye-tracker, a research tool used to show where the eye is looking at a particular screen, thanks to teammate Michael LaDuke. Dionne Healy, HCM Client Executive, and Aylin Uysal, Director, HCM Cloud user experiences, Oracle, take a look at new HCM Cloud UX concepts. We closed the day with Jeremy Ashley (@jrwashley), VP, Applications User Experience, who brought it all back together by talking about the big picture for applications cloud user experiences. He covered the trends we are paying attention to now, what users will be expecting of their modern enterprise apps, and what Oracle’s design strategy is around these ideas.   We closed with an excellent reception hosted by ADP Payroll services at Bistango. Want to read more?Want to see where our cloud user experience is going next? Read more on the UsableApps web site about our latest design initiative: “Glance, Scan, Commit.” Or catch up on the back story by looking over our Applications Cloud user experience content on the UsableApps web site.  You can also find out where we’ll be next at the Events page on UsableApps.

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• Finding a person in the forest

  - by PointsToShare

  © 2011 By: Dov Trietsch. All rights reserved finding a person in the forest or Limiting the AD result in SharePoint People Picker There are times when we need to limit the SharePoint audience of certain farms or servers or site collections to a particular audience. One of my experiences involved limiting access to US citizens, another to a particular location. Now, most of us – your humble servant included – are not Active Directory experts – but we must be able to handle the “audience restrictions” as required. So here is how it’s done in a nutshell. Important note. Not all could be done in PowerShell (at least not yet)! There are no Windows PowerShell commands to configure People Picker. The stsadm command is: stsadm -o setproperty -pn peoplepicker-searchadcustomquery -pv ADQuery –url http://somethingOrOther Note the long-hyphenated property name. Now to filling the ADQuery.   LDAP Query in a nutshell Syntax LDAP is no older than SQL and an LDAP query is actually a query against the LDAP Database. LDAP attributes are the equivalent of Database columns, so why do we have to learn a new query language? Beats me! But we must, so here it is. The syntax of an LDAP query string is made of individual statements with relational operators including: = Equal <= Lower than or equal >= Greater than or equal… and memberOf – a group membership. ! Not * Wildcard Equal and memberOf are the most commonly used. Checking for absence uses the ! – not and the * - wildcard Example: (SN=Grant) All whose last name – SurName – is Grant Example: (!(SN=Grant)) All except Grant Example: (!(SN=*)) all where there is no SurName i.e SurName is absent (probably Rappers). Example: (CN=MyGroup) Common Name is MyGroup.  Example: (GN=J*) all the Given Names that start with J (JJ, Jane, Jon, John, etc.) The cryptic SN, CN, GN, etc. are attributes and more about them later All the queries are enclosed in parentheses (Query). Complex queries are comprised of sets that are in AND or OR conditions. AND is denoted by the ampersand (&) and the OR is denoted by the vertical pipe (|). The general syntax is that of the Prefix polish notation where the operand precedes the variables. E.g +ab is the sum of a and b. In an LDAP query (&(A)(B)) will garner the objects for which both A and B are true. In an LDAP query (&(A)(B)(C)) will garner the objects for which A, B and C are true. There’s no limit to the number of conditions. In an LDAP query (|(A)(B)) will garner the objects for which either A or B are true. In an LDAP query (|(A)(B)(C)) will garner the objects for which at least one of A, B and C is true. There’s no limit to the number of conditions. More complex queries have both types of conditions and the parentheses determine the order of operations. Attributes Now let’s get into the SN, CN, GN, and other attributes of the query SN – is the SurName (last name) GN – is the Given Name (first name) CN – is the Common Name, usually GN followed by SN OU – is an Organization Unit such as division, department etc. DC – is a Domain Content in the AD forest l – lower case ‘L’ stands for location. Jerusalem anybody? Or Katmandu. UPN – User Principal Name, is usually the first part of an email address. By nature it is unique in the forest. Most systems set the UPN to be the first initial followed by the SN of the person involved. Some limit the total to 8 characters. If we have many ‘jsmith’ we have to somehow distinguish them from each other. DN – is the distinguished name – a name unique to AD forest in which it lives. Usually it’s a CN with some domain or group distinguishers. DN is important in conjunction with the memberOf relation. Groups have stricter requirement. Each group has to have a unique name - its CN and it has to be unique regardless of its place. See more below. All of the attributes are case insensitive. CN, cn, Cn, and cN are identical. objectCategory is an element that requires special consideration. AD contains many different object like computers, printers, and of course people and groups. In the queries below, we’re limiting our search to people (person). Putting it altogether Let’s get a list of all the Johns in the SPAdmin group of the Jerusalem that local domain. (&(objectCategory=person)(memberOf=cn=SPAdmin,ou=Jerusalem,dc=local)) The memberOf=cn=SPAdmin uses the cn (Common Name) of the SPAdmin group. This is how the memberOf relation is used. ‘SPAdmin’ is actually the DN of the group. Also the memberOf relation does not allow wild cards (*) in the group name. Also, you are limited to at most one ‘OU’ entry. Let’s add Marvin Minsky to the search above. |(&(objectCategory=person)(memberOf=cn=SPAdmin,ou=Jerusalem,dc=local))(CN=Marvin Minsky) Here I added the or pipeline at the beginning of the query and put the CN requirement for Minsky at the end. Note that if Marvin was already in the prior result, he’s not going to be listed twice. One last note: You may see a dryer but more complete list of attributes rules and examples in: http://www.tek-tips.com/faqs.cfm?fid=5667 And finally (thus negating the claim that my previous note was last), to the best of my knowledge there are 3 more ways to limit the audience. One is to use the peoplepicker-searchadcustomfilter property using the same ADQuery. This works only in SP1 and above. The second is to limit the search to users within this particular site collection – the property name is peoplepicker-onlysearchwithinsitecollection and the value is yes (-pv yes) And the third is –pn peoplepicker-serviceaccountdirectorypaths –pv “OU=ou1,DC=dc1…..” Again you are limited to at most one ‘OU’ phrase – no OU=ou1,OU=ou2… And now the real end. The main property discussed in this sprawling and seemingly endless monogram – peoplepicker-searchadcustomquery - is the most general way of getting the job done. Here are a few examples of command lines that worked and some that didn’t. Can you see why? C:\Program Files\Common Files\Microsoft Shared\Web Server Extensions\12\BIN>stsa dm -o setproperty -url http://somethingOrOther -pn peoplepicker-searchadcustomfi lter -pv (Title=David) Operation completed successfully. C:\Program Files\Common Files\Microsoft Shared\Web Server Extensions\12\BIN>stsa dm -o setproperty -url http://somethingOrOther -pn peoplepicker-searchadcustomfi lter -pv (!Title=David) Operation completed successfully. C:\Program Files\Common Files\Microsoft Shared\Web Server Extensions\12\BIN>stsa dm -o setproperty -url http://somethingOrOther -pn peoplepicker-searchadcustomfi lter -pv (OU=OURealName,OU=OUMid,OU=OUTop,DC=TopDC,DC=MidDC,DC=BottomDC) Command line error. Too many OUs C:\Program Files\Common Files\Microsoft Shared\Web Server Extensions\12\BIN>stsa dm -o setproperty -url http://somethingOrOther -pn peoplepicker-searchadcustomfi lter -pv (OU=OURealName) Operation completed successfully. C:\Program Files\Common Files\Microsoft Shared\Web Server Extensions\12\BIN>stsa dm -o setproperty -url http://somethingOrOther -pn peoplepicker-searchadcustomfi lter -pv (DC=TopDC,DC=MidDC,DC=BottomDC) Operation completed successfully. C:\Program Files\Common Files\Microsoft Shared\Web Server Extensions\12\BIN>stsa dm -o setproperty -url http://somethingOrOther -pn peoplepicker-searchadcustomfi lter -pv (OU=OURealName,DC=TopDC,DC=MidDC,DC=BottomDC) Operation completed successfully.   That’s all folks!

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• How can a code editor effectively hint at code nesting level - without using indentation?

  - by pgfearo

  I've written an XML text editor that provides 2 view options for the same XML text, one indented (virtually), the other left-justified. The motivation for the left-justified view is to help users 'see' the whitespace characters they're using for indentation of plain-text or XPath code without interference from indentation that is an automated side-effect of the XML context. I want to provide visual clues (in the non-editable part of the editor) for the left-justified mode that will help the user, but without getting too elaborate. I tried just using connecting lines, but that seemed too busy. The best I've come up with so far is shown in a mocked up screenshot of the editor below, but I'm seeking better/simpler alternatives (that don't require too much code). [Edit] Taking the heatmap idea (from: @jimp) I get this and 3 alternatives - labelled a, b and c: The following section describes the accepted answer as a proposal, bringing together ideas from a number of other answers and comments. As this question is now community wiki, please feel free to update this. NestView The name for this idea which provides a visual method to improve the readability of nested code without using indentation. Contour Lines The name for the differently shaded lines within the NestView The image above shows the NestView used to help visualise an XML snippet. Though XML is used for this illustration, any other code syntax that uses nesting could have been used for this illustration. An Overview: The contour lines are shaded (as in a heatmap) to convey nesting level The contour lines are angled to show when a nesting level is being either opened or closed. A contour line links the start of a nesting level to the corresponding end. The combined width of contour lines give a visual impression of nesting level, in addition to the heatmap. The width of the NestView may be manually resizable, but should not change as the code changes. Contour lines can either be compressed or truncated to keep acheive this. Blank lines are sometimes used code to break up text into more digestable chunks. Such lines could trigger special behaviour in the NestView. For example the heatmap could be reset or a background color contour line used, or both. One or more contour lines associated with the currently selected code can be highlighted. The contour line associated with the selected code level would be emphasized the most, but other contour lines could also 'light up' in addition to help highlight the containing nested group Different behaviors (such as code folding or code selection) can be associated with clicking/double-clicking on a Contour Line. Different parts of a contour line (leading, middle or trailing edge) may have different dynamic behaviors associated. Tooltips can be shown on a mouse hover event over a contour line The NestView is updated continously as the code is edited. Where nesting is not well-balanced assumptions can be made where the nesting level should end, but the associated temporary contour lines must be highlighted in some way as a warning. Drag and drop behaviors of Contour Lines can be supported. Behaviour may vary according to the part of the contour line being dragged. Features commonly found in the left margin such as line numbering and colour highlighting for errors and change state could overlay the NestView. Additional Functionality The proposal addresses a range of additional issues - many are outside the scope of the original question, but a useful side-effect. Visually linking the start and end of a nested region The contour lines connect the start and end of each nested level Highlighting the context of the currently selected line As code is selected, the associated nest-level in the NestView can be highlighted Differentiating between code regions at the same nesting level In the case of XML different hues could be used for different namespaces. Programming languages (such as c#) support named regions that could be used in a similar way. Dividing areas within a nesting area into different visual blocks Extra lines are often inserted into code to aid readability. Such empty lines could be used to reset the saturation level of the NestView's contour lines. Multi-Column Code View Code without indentation makes the use of a multi-column view more effective because word-wrap or horizontal scrolling is less likely to be required. In this view, once code has reach the bottom of one column, it flows into the next one: Usage beyond merely providing a visual aid As proposed in the overview, the NestView could provide a range of editing and selection features which would be broadly in line with what is expected from a TreeView control. The key difference is that a typical TreeView node has 2 parts: an expander and the node icon. A NestView contour line can have as many as 3 parts: an opener (sloping), a connector (vertical) and a close (sloping). On Indentation The NestView presented alongside non-indented code complements, but is unlikely to replace, the conventional indented code view. It's likely that any solutions adopting a NestView, will provide a method to switch seamlessly between indented and non-indented code views without affecting any of the code text itself - including whitespace characters. One technique for the indented view would be 'Virtual Formatting' - where a dynamic left-margin is used in lieu of tab or space characters. The same nesting-level data used to dynamically render the NestView could also used for the more conventional-looking indented view. Printing Indentation will be important for the readability of printed code. Here, the absence of tab/space characters and a dynamic left-margin means that the text can wrap at the right-margin and still maintain the integrity of the indented view. Line numbers can be used as visual markers that indicate where code is word-wrapped and also the exact position of indentation: Screen Real-Estate: Flat Vs Indented Addressing the question of whether the NestView uses up valuable screen real-estate: Contour lines work well with a width the same as the code editor's character width. A NestView width of 12 character widths can therefore accommodate 12 levels of nesting before contour lines are truncated/compressed. If an indented view uses 3 character-widths for each nesting level then space is saved until nesting reaches 4 levels of nesting, after this nesting level the flat view has a space-saving advantage that increases with each nesting level. Note: A minimum indentation of 4 character widths is often recommended for code, however XML often manages with less. Also, Virtual Formatting permits less indentation to be used because there's no risk of alignment issues A comparison of the 2 views is shown below: Based on the above, its probably fair to conclude that view style choice will be based on factors other than screen real-estate. The one exception is where screen space is at a premium, for example on a Netbook/Tablet or when multiple code windows are open. In these cases, the resizable NestView would seem to be a clear winner. Use Cases Examples of real-world examples where NestView may be a useful option: Where screen real-estate is at a premium a. On devices such as tablets, notepads and smartphones b. When showing code on websites c. When multiple code windows need to be visible on the desktop simultaneously Where consistent whitespace indentation of text within code is a priority For reviewing deeply nested code. For example where sub-languages (e.g. Linq in C# or XPath in XSLT) might cause high levels of nesting. Accessibility Resizing and color options must be provided to aid those with visual impairments, and also to suit environmental conditions and personal preferences: Compatability of edited code with other systems A solution incorporating a NestView option should ideally be capable of stripping leading tab and space characters (identified as only having a formatting role) from imported code. Then, once stripped, the code could be rendered neatly in both the left-justified and indented views without change. For many users relying on systems such as merging and diff tools that are not whitespace-aware this will be a major concern (if not a complete show-stopper). Other Works: Visualisation of Overlapping Markup Published research by Wendell Piez, dated from 2004, addresses the issue of the visualisation of overlapping markup, specifically LMNL. This includes SVG graphics with significant similarities to the NestView proposal, as such, they are acknowledged here. The visual differences are clear in the images (below), the key functional distinction is that NestView is intended only for well-nested XML or code, whereas Wendell Piez's graphics are designed to represent overlapped nesting. The graphics above were reproduced - with kind permission - from http://www.piez.org Sources: Towards Hermenutic Markup Half-steps toward LMNL

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• Product Development Investment: A Measure of Vendor Performance

  - by Jim Mcglothlin

  The relationship between a large, complex organization and its key suppliers of information technology is normally more than just "strategic". Expectations about the duration of the relationship typically exceed 20 years. Enterprise applications and technology infrastructure are not expected to be changed out like petunias. So how would you rate the due diligence processes as performed in Higher Education when selecting critical, transformational information technology? My observation: I see a lot of effort put into elaborate demonstration of basic software functionality. I see a lot of attention paid to the cost element of technology acquisition, including the contracted cost of implementation consulting services. But the factor that receives only cursory analysis and due diligence is long-term performance--the ability of a vendor to grow, expand, and develop, and bring its customers along with it. So what should you look for in a long-term IT supplier? Oracle has a public track record for product development. The annual investment has been on a run rate of almost $3 Billion organic product development. Oracle's well-publicized acquisitions and mergers have been supplemental to its R&D. This is important for Higher Education. Another meaningful way to evaluate a company is to look at the tangible track record of enhancement. Consider the Oracle-PeopleSoft enterprise business platform since acquired by Oracle 6 years ago: Product or Technology Enhancement Customer or User Impact Service Oriented Architecture (SOA) 300+ new web services delivered in versions 9.0 & 9.1 provide flexibility, so that customers can integrate PeopleSoft with other applications. Campus Solutions has added Admissions and Constituent Web Services. Constituent Relationship Management PeopleSoft CRM 9.1 for Higher Education introduced new process flows for student recruiting and retention to support "Student Success" initiatives. A 360 view of the constituent is now delivered, and the concept of a single-stop Student Services Center is now in CRM 9.1 with tight integration to PeopleSoft Campus Solutions. Human Capital Management Contract Pay for Education, with flexibility for configuration and calculation, has been extended in HCM 9.1. New chartfield integration among Project Costing - Time & Labor - Payroll to serve the labor distribution requirements for Grants / Sponsored Research. Talent Management PeopleSoft 9.0 and 9.1 feature an integrated talent management approach centered on definitions in "Profile Manager", with all new usability improvements. Internal and external candidate pools, and the entire recruitment process, are driven by delivered configurable selection and on-boarding processes. Interview scheduling, and online job offers are newly delivered processes. Performance Management PeopleSoft HCM ePerformance 9.1 will include significant new functionality designed to help organizations more effectively align business objectives with employee goals. Using an Organization Chart view, your business goals can flow down to become tangible objectives per employee. Succession Planning / Workforce Development New in HCM 9.0, enhanced in 9.1, is a planning capability for regular or unusual (major organizational change) succession of internal or external candidates. PeopleSoft supports employee-based career planning, which ultimately increases the integrity of the succession planning process (identify their career needs, plans, preferences, and interests). Dashboards / Oracle Business Intelligence Application Suite Oracle Human Resources Analytics provides the workforce information foundation that integrates data from HR functional areas and Finance. Oracle Human Resources Analytics delivers 9 dashboards and over 200 reports. Provide your HR professionals and front-line managers the tools to analyze workforce staffing, retention, productivity, to better source high-quality applicants, and to reduce absence costs. Multi-year Planning and Commitment Control External funding sources, especially Grants, require a multi-year encumbrance business process. PeopleSoft HCM 9.1 adds multi-year funding and commitment control, including budget checking. The newly designed Real Time Budget Checking will provide the customer with an updated snapshot of their budget and encumbrances at any given time. Position Budgeting with Hyperion Hyperion Planning world-class products now include delivered integration to PeopleSoft HCM. Position Budgeting is available in the new Public Sector Planning module of Hyperion. Web 2.0 features for the latest in usability PeopleSoft 9.1 features a contemporary internet user experience: Partial-page refreshing Drag and drop pagelets New menu structure Navigation pagelets Modal popup message windows Favorites & recently used links Type-ahead Drag and drop grid columns, pop-out grids Portal Workspaces Enterprise 2.0 for your collaborative web communities, using new content management, along with Wikis, blogs, and discussion forums in PeopleSoft Portal 9.1. PeopleTools enhanced by Oracle Fusion Middleware Standards-based tools have been added to the PeopleTools application infrastructure: BI (XML) Publisher, Java tools. Certified for use with PeopleSoft: Oracle Business Intelligence (OBIEE), Oracle Enterprise Manager, Oracle Weblogic Server, Oracle SOA Suite. Hosting for PeopleSoft applications A solid new deployment option: Oracle On Demand remote hosting center for high scalability, security, and continuity of operations. Business Process Outsourcing (BPO) for HCM / Payroll functions Partnership with AT&T provides hosting of HR/Payroll application along with payroll business process operations, and subscription-based service fees (SaaS). AT&T BPO full service includes pay sheet processing, bank and 3rd party file transfer, payroll tax handling, etc. Continuous Delivery Model Feature Packs provide faster time-to-benefit; new features become available in PeopleSoft 9.1 (or Campus Solutions 9.0) without need to perform upgrade. Golden person data model across all campus applications Oracle Higher Education Constituent Hub provides synchronization and data governance of person data across any application, e.g. HR/ Payroll, Student Information System, Housing, Emergency Contact, LMS, CRM. Oracle's aggressive enhancement plans within the "Applications Unlimited" program continue, as new functionality is under development for a new version of a PeopleSoft release planned for 2012. Meanwhile, new capabilities are planned on an annual basis in Feature Packs. PeopleSoft just delivered the HCM 2010 Feature Pack and another is planned for 2011. In February we plan to have over 100 customers from our Customer Advisory Boards at our PeopleSoft Development Center in California to review designs for all of these releases. For those of you near New York City The investment and progressive development story described above is the subject of an Oracle road show event on February 9, 2011. Charting Your Course with Oracle Applications is a global event series designed to help business and IT executives assess the impact of new inflection points on their business and applications roadmap: changing workforces, shifting customer and constituent bases, and increased volatility. Learn how innovations ranging from new deployment models like cloud computing to the introduction of social applications and smart devices are delivering results across all areas of business and industry. THIS DOCUMENT IS FOR INFORMATIONAL PURPOSES ONLY AND MAY NOT BE INCORPORATED INTO A CONTRACT OR AGREEMENT.

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• Inheritance Mapping Strategies with Entity Framework Code First CTP5: Part 2 – Table per Type (TPT)

  - by mortezam

  In the previous blog post you saw that there are three different approaches to representing an inheritance hierarchy and I explained Table per Hierarchy (TPH) as the default mapping strategy in EF Code First. We argued that the disadvantages of TPH may be too serious for our design since it results in denormalized schemas that can become a major burden in the long run. In today’s blog post we are going to learn about Table per Type (TPT) as another inheritance mapping strategy and we'll see that TPT doesn’t expose us to this problem. Table per Type (TPT)Table per Type is about representing inheritance relationships as relational foreign key associations. Every class/subclass that declares persistent properties—including abstract classes—has its own table. The table for subclasses contains columns only for each noninherited property (each property declared by the subclass itself) along with a primary key that is also a foreign key of the base class table. This approach is shown in the following figure: For example, if an instance of the CreditCard subclass is made persistent, the values of properties declared by the BillingDetail base class are persisted to a new row of the BillingDetails table. Only the values of properties declared by the subclass (i.e. CreditCard) are persisted to a new row of the CreditCards table. The two rows are linked together by their shared primary key value. Later, the subclass instance may be retrieved from the database by joining the subclass table with the base class table. TPT Advantages The primary advantage of this strategy is that the SQL schema is normalized. In addition, schema evolution is straightforward (modifying the base class or adding a new subclass is just a matter of modify/add one table). Integrity constraint definition are also straightforward (note how CardType in CreditCards table is now a non-nullable column). Another much more important advantage is the ability to handle polymorphic associations (a polymorphic association is an association to a base class, hence to all classes in the hierarchy with dynamic resolution of the concrete class at runtime). A polymorphic association to a particular subclass may be represented as a foreign key referencing the table of that particular subclass. Implement TPT in EF Code First We can create a TPT mapping simply by placing Table attribute on the subclasses to specify the mapped table name (Table attribute is a new data annotation and has been added to System.ComponentModel.DataAnnotations namespace in CTP5): public abstract class BillingDetail {     public int BillingDetailId { get; set; }     public string Owner { get; set; }     public string Number { get; set; } } [Table("BankAccounts")] public class BankAccount : BillingDetail {     public string BankName { get; set; }     public string Swift { get; set; } } [Table("CreditCards")] public class CreditCard : BillingDetail {     public int CardType { get; set; }     public string ExpiryMonth { get; set; }     public string ExpiryYear { get; set; } } public class InheritanceMappingContext : DbContext {     public DbSet<BillingDetail> BillingDetails { get; set; } } If you prefer fluent API, then you can create a TPT mapping by using ToTable() method: protected override void OnModelCreating(ModelBuilder modelBuilder) {     modelBuilder.Entity<BankAccount>().ToTable("BankAccounts");     modelBuilder.Entity<CreditCard>().ToTable("CreditCards"); } Generated SQL For QueriesLet’s take an example of a simple non-polymorphic query that returns a list of all the BankAccounts: var query = from b in context.BillingDetails.OfType<BankAccount>() select b; Executing this query (by invoking ToList() method) results in the following SQL statements being sent to the database (on the bottom, you can also see the result of executing the generated query in SQL Server Management Studio): Now, let’s take an example of a very simple polymorphic query that requests all the BillingDetails which includes both BankAccount and CreditCard types: projects some properties out of the base class BillingDetail, without querying for anything from any of the subclasses: var query = from b in context.BillingDetails             select new { b.BillingDetailId, b.Number, b.Owner }; -- var query = from b in context.BillingDetails select b; This LINQ query seems even more simple than the previous one but the resulting SQL query is not as simple as you might expect: -- As you can see, EF Code First relies on an INNER JOIN to detect the existence (or absence) of rows in the subclass tables CreditCards and BankAccounts so it can determine the concrete subclass for a particular row of the BillingDetails table. Also the SQL CASE statements that you see in the beginning of the query is just to ensure columns that are irrelevant for a particular row have NULL values in the returning flattened table. (e.g. BankName for a row that represents a CreditCard type) TPT ConsiderationsEven though this mapping strategy is deceptively simple, the experience shows that performance can be unacceptable for complex class hierarchies because queries always require a join across many tables. In addition, this mapping strategy is more difficult to implement by hand— even ad-hoc reporting is more complex. This is an important consideration if you plan to use handwritten SQL in your application (For ad hoc reporting, database views provide a way to offset the complexity of the TPT strategy. A view may be used to transform the table-per-type model into the much simpler table-per-hierarchy model.) SummaryIn this post we learned about Table per Type as the second inheritance mapping in our series. So far, the strategies we’ve discussed require extra consideration with regard to the SQL schema (e.g. in TPT, foreign keys are needed). This situation changes with the Table per Concrete Type (TPC) that we will discuss in the next post. References ADO.NET team blog Java Persistence with Hibernate book a { text-decoration: none; } a:visited { color: Blue; } .title { padding-bottom: 5px; font-family: Segoe UI; font-size: 11pt; font-weight: bold; padding-top: 15px; } .code, .typeName { font-family: consolas; } .typeName { color: #2b91af; } .padTop5 { padding-top: 5px; } .padTop10 { padding-top: 10px; } p.MsoNormal { margin-top: 0in; margin-right: 0in; margin-bottom: 10.0pt; margin-left: 0in; line-height: 115%; font-size: 11.0pt; font-family: "Calibri" , "sans-serif"; }

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• 5 Best Practices - Laying the Foundation for WebCenter Projects

  - by Kellsey Ruppel

  Today’s guest post comes from Oracle WebCenter expert John Brunswick. John specializes in enterprise portal and content management solutions and actively contributes to the enterprise software business community and has authored a series of articles about optimal business involvement in portal, business process management and SOA development, examining ways of helping organizations move away from monolithic application development. We’re happy to have John join us today! Maximizing success with Oracle WebCenter portal requires a strategic understanding of Oracle WebCenter capabilities.  The following best practices enable the creation of portal solutions with minimal resource overhead, while offering the greatest flexibility for progressive elaboration. They are inherently project agnostic, enabling a strong foundation for future growth and an expedient return on your investment in the platform.  If you are able to embrace even only a few of these practices, you will materially improve your deployment capability with WebCenter. 1. Segment Duties Around 3Cs - Content, Collaboration and Contextual Data "Agility" is one of the most common business benefits touted by modern web platforms.  It sounds good - who doesn't want to be Agile, right?  How exactly IT organizations go about supplying agility to their business counterparts often lacks definition - hamstrung by ambiguity. Ultimately, businesses want to benefit from reduced development time to deliver a solution to a particular constituent, which is augmented by as much self-service as possible to develop and manage the solution directly. All done in the absence of direct IT involvement. With Oracle WebCenter's depth in the areas of content management, pallet of native collaborative services, enterprise mashup capability and delegated administration, it is very possible to execute on this business vision at a technical level. To realize the benefits of the platform depth we can think of Oracle WebCenter's segmentation of duties along the lines of the 3 Cs - Content, Collaboration and Contextual Data.  All three of which can have their foundations developed by IT, then provisioned to the business on a per role basis. Content – Oracle WebCenter benefits from an extremely mature content repository.  Work flow, audit, notification, office integration and conversion capabilities for documents (HTML & PDF) make this a haven for business users to take control of content within external and internal portals, custom applications and web sites.  When deploying WebCenter portal take time to think of areas in which IT can provide the "harness" for content to reside, then allow the business to manage any content items within the site, using the content foundation to ensure compliance with business rules and process.  This frees IT to work on more mission critical challenges and allows the business to respond in short order to emerging market needs. Collaboration – Native collaborative services and WebCenter spaces are a perfect match for business users who are looking to enable document sharing, discussions and social networking.  The ability to deploy the services is granular and on the basis of roles scoped to given areas of the system - much like the first C “content”.  This enables business analysts to design the roles required and IT to provision with peace of mind that users leveraging the collaborative services are only able to do so in explicitly designated areas of a site. Bottom line - business will not need to wait for IT, but cannot go outside of the scope that has been defined based on their roles. Contextual Data – Collaborative capabilities are most powerful when included within the context of business data.  The ability to supply business users with decision shaping data that they can include in various parts of a portal or portals, just as they would with content items, is one of the most powerful aspects of Oracle WebCenter.  Imagine a discussion about new store selection for a retail chain that re-purposes existing information from business intelligence services about various potential locations and or custom backend systems - presenting it directly in the context of the discussion.  If there are some data sources that are preexisting in your enterprise take a look at how they can be made into discrete offerings within the portal, then scoped to given business user roles for inclusion within collaborative activities. 2. Think Generically, Execute Specifically Constructs.  Anyone who has spent much time around me knows that I am obsessed with this word.  Why? Because Constructs offer immense power - more than APIs, Web Services or other technical capability. Constructs offer organizations the ability to leverage a platform's native characteristics to offer substantial business functionality - without writing code.  This concept becomes more powerful with the additional understanding of the concepts from the platform that an organization learns over time.  Let's take a look at an example of where an Oracle WebCenter construct can substantially reduce the time to get a subscription-based site out the door and into the hands of the end consumer. Imagine a site that allows members to subscribe to specific disciplines to access information and application data around that various discipline.  A space is a collection of secured pages within Oracle WebCenter.  Spaces are not only secured, but also default content stored within it to be scoped automatically to that space. Taking this a step further, Oracle WebCenter’s Activity Stream surfaces events, discussions and other activities that are scoped to the given user on the basis of their space affiliations.  In order to have a portal that would allow users to "subscribe" to information around various disciplines - spaces could be used out of the box to achieve this capability and without using any APIs or low level technical work to achieve this. 3. Make Governance Work for You Imagine driving down the street without the painted lines on the road.  The rules of the road are so ingrained in our minds, we often do not think about the process, but seemingly mundane lane markers are critical enablers. Lane markers allow us to travel at speeds that would be impossible if not for the agreed upon direction of flow. Additionally and more importantly, it allows people to act autonomously - going where they please at any given time. The return on the investment for mobility is high enough for people to buy into globally agreed up governance processes. In Oracle WebCenter we can use similar enablers to lane markers.  Our goal should be to enable the flow of information and provide end users with the ability to arrive at business solutions as needed, not on the basis of cumbersome processes that cannot meet the business needs in a timely fashion. How do we do this? Just as with "Segmentation of Duties" Oracle WebCenter technologies offer the opportunity to compartmentalize various business initiatives from each other within the system due to constructs and security that are available to use within the platform. For instance, when a WebCenter space is created, any content added within that space by default will be secured to that particular space and inherits meta data that is associated with a folder created for the space. Oracle WebCenter content uses meta data to support a broad range of rich ECM functionality and can automatically impart retention, workflow and other policies automatically on the basis of what has been defaulted for that space. Depending on your business needs, this paradigm will also extend to sub sections of a space, offering some interesting possibilities to enable automated management around content. An example may be press releases within a particular area of an extranet that require a five year retention period and need to the reviewed by marketing and legal before release.  The underlying content system will transparently take care of this process on the basis of the above rules, enabling peace of mind over unstructured data - which could otherwise become overwhelming. 4. Make Your First Project Your Second Imagine if Michael Phelps was competing in a swimming championship, but told right before his race that he had to use a brand new stroke.  There is no doubt that Michael is an outstanding swimmer, but chances are that he would like to have some time to get acquainted with the new stroke. New technologies should not be treated any differently.  Before jumping into the deep end it helps to take time to get to know the new approach - even though you may have been swimming thousands of times before. To quickly get a handle on Oracle WebCenter capabilities it can be helpful to deploy a sandbox for the team to use to share project documents, discussions and announcements in an effort to help the actual deployment get under way, while increasing everyone’s knowledge of the platform and its functionality that may be helpful down the road. Oracle Technology Network has made a pre-configured virtual machine available for download that can be a great starting point for this exercise. 5. Get to Know the Community If you are reading this blog post you have most certainly faced a software decision or challenge that was solved on the basis of a small piece of missing critical information - which took substantial research to discover.  Chances were also good that somewhere, someone had already come across this information and would have been excited to share it. There is no denying the power of passionate, connected users, sharing key tips around technology.  The Oracle WebCenter brand has a rich heritage that includes industry-leading technology and practitioners.  With the new Oracle WebCenter brand, opportunities to connect with these experts has become easier. Oracle WebCenter Blog Oracle Social Enterprise LinkedIn WebCenter Group Oracle WebCenter Twitter Oracle WebCenter Facebook Oracle User Groups Additionally, there are various Oracle WebCenter related blogs by an excellent grouping of services partners.

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• Unicast traffic between hosts on a switch leaving the switch by its uplink. Why?

  - by Rich Lafferty

  I have a weird thing happening on our network at my office which I can't quite get my head around. In particular I can't tell if it's a problem with a switch, or a problem with configuration. We have a Cisco SG300-52 switch (sw01) in the top of a rack in our server room, connected to another SG300-28 that acts as our core switch (core01). Both run layer 2 only, our firewalls do routing between VLANs. They have a dozen or so VLANs between them. Gi1 on sw01 is a trunk port connected to gi1 on core01. (Disclosure: There are other switches in our environment but I'm pretty sure I've isolated the problem down to these two. Happy to provide more info if necessary.) The behaviour I'm seeing is limited to one VLAN, vlan 12 -- or, at least, it's not happening on the other ones I checked (It's hard to guarantee the absence of packets), and it is: sw01 is forwarding, to core01, traffic which is between two hosts which are both plugged into sw01. (I noticed this because the IDS in our firewall gave a false positive on traffic which should not reach the firewall.) We noticed this mostly between our two dhcp/dns servers, net01 (10.12.0.10) and net02 (10.12.0.11). net01 is physical hardware and net02 is on a VMware ESX server. net01 is connected to gi44 on sw01 and net02's ESX server to gi11. [net01]----gi44-[sw01]-gi1----gi1-[core01] [net02]----gi11/ Let's see some interfaces! Remember, vlan 12 is the problem vlan. Of the others I explicitly verified that vlan 27 was not affected. Here's the two hosts' ports: esx01 contains net02. sw01#sh run int gi11 interface gigabitethernet11 description esx01 lldp med disable switchport trunk allowed vlan add 5-7,11-13,100 switchport trunk native vlan 27 ! sw01#sh run int gi44 interface gigabitethernet44 description net01-1 lldp med disable switchport mode access switchport access vlan 12 ! Here's the trunk on sw01. sw01#sh run int gi1 interface gigabitethernet1 description "trunk to core01" lldp med disable switchport trunk allowed vlan add 4-7,11-13,27,100 ! And the other end of the trunk on core01. interface gigabitethernet1 description sw01 macro description switch switchport trunk allowed vlan add 2-7,11-16,27,100 ! I have a monitor port on core01, thus: core01#sh run int gi12 interface gigabitethernet12 description "monitor port" port monitor GigabitEthernet 1 ! And the monitor port on core01 sees unicast traffic going between net01 and net02, both of which are on sw01! I've verified this with a monitor port on sw01 that sees the net01-net02 unicast traffic leaving via gi1 too. sw01 knows that both of those hosts are on ports that are not its trunk port: :) ratchet$ arp -a | grep net net02.2ndsiteinc.com (10.12.0.11) at 00:0C:29:1A:66:15 [ether] on eth0 net01.2ndsiteinc.com (10.12.0.10) at 00:11:43:D8:9F:94 [ether] on eth0 sw01#sh mac addr addr 00:0C:29:1A:66:15 Aging time is 300 sec Vlan Mac Address Port Type -------- --------------------- ---------- ---------- 12 00:0c:29:1a:66:15 gi11 dynamic sw01#sh mac addr addr 00:11:43:D8:9F:94 Aging time is 300 sec Vlan Mac Address Port Type -------- --------------------- ---------- ---------- 12 00:11:43:d8:9f:94 gi44 dynamic I also brought up an unused port on sw01 on vlan 12, but the unicast traffic was (as best as I could tell) not coming out that port. So it doesn't look like sw01 is pushing it out all its ports, just the right ports and also gi1! I've verified that sw01 is not filling up its address-table: sw01#sh mac addr count This may take some time. Capacity : 8192 Free : 7983 Used : 208 The full configs for both core01 and sw01 are available: core01, sw01. Finally, versions: sw01#sh ver SW version 1.1.2.0 ( date 12-Nov-2011 time 23:34:26 ) Boot version 1.0.0.4 ( date 08-Apr-2010 time 16:37:57 ) HW version V01 core01#sh ver SW version 1.1.2.0 ( date 12-Nov-2011 time 23:34:26 ) Boot version 1.1.0.6 ( date 11-May-2011 time 18:31:00 ) HW version V01 So my understanding is this: sw01 should take unicast traffic for net01 and send it only out net02's port, and vice versa; none of it should go out sw01's uplink. But core01, receiving traffic on gi1 for a host it knows is on gi1, is right in sending it out all of its ports. (That is: sw01 is misbehaving, but core01 is doing what it should given the circumstances.) My question is: Why is sw01 sending that unicast traffic out its uplink, gi1? (And pre-emptively: yes, I know SG300s leave much to be desired, and yes, we should have spanning-tree enabled, but that's where I'm at right now.)

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