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• Implementing Skip List in C++

  - by trikker

  [SOLVED] So I decided to try and create a sorted doubly linked skip list... I'm pretty sure I have a good grasp of how it works. When you insert x the program searches the base list for the appropriate place to put x (since it is sorted), (conceptually) flips a coin, and if the "coin" lands on a then that element is added to the list above it(or a new list is created with element in it), linked to the element below it, and the coin is flipped again, etc. If the "coin" lands on b at anytime then the insertion is over. You must also have a -infinite stored in every list as the starting point so that it isn't possible to insert a value that is less than the starting point (meaning that it could never be found.) To search for x, you start at the "top-left" (highest list lowest value) and "move right" to the next element. If the value is less than x than you continue to the next element, etc. until you have "gone too far" and the value is greater than x. In this case you go back to the last element and move down a level, continuing this chain until you either find x or x is never found. To delete x you simply search x and delete it every time it comes up in the lists. For now, I'm simply going to make a skip list that stores numbers. I don't think there is anything in the STL that can assist me, so I will need to create a class List that holds an integer value and has member functions, search, delete, and insert. The problem I'm having is dealing with links. I'm pretty sure I could create a class to handle the "horizontal" links with a pointer to the previous element and the element in front, but I'm not sure how to deal with the "vertical" links (point to corresponding element in other list?) If any of my logic is flawed please tell me, but my main questions are: How to deal with vertical links and whether my link idea is correct Now that I read my class List idea I'm thinking that a List should hold a vector of integers rather than a single integer. In fact I'm pretty positive, but would just like some validation. I'm assuming the coin flip would simply call int function where rand()%2 returns a value of 0 or 1 and if it's 0 then a the value "levels up" and if it's 0 then the insert is over. Is this incorrect? How to store a value similar to -infinite? Edit: I've started writing some code and am considering how to handle the List constructor....I'm guessing that on its construction, the "-infinite" value should be stored in the vectorname[0] element and I can just call insert on it after its creation to put the x in the appropriate place.

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• Should I create a unique clustered index, or non-unique clustered index on this SQL 2005 table?

  - by Bremer

  I have a table storing millions of rows. It looks something like this: Table_Docs ID, Bigint (Identity col) OutputFileID, int Sequence, int …(many other fields) We find ourselves in a situation where the developer who designed it made the OutputFileID the clustered index. It is not unique. There can be thousands of records with this ID. It has no benefit to any processes using this table, so we plan to remove it. The question, is what to change it to… I have two candidates, the ID identity column is a natural choice. However, we have a process which does a lot of update commands on this table, and it uses the Sequence to do so. The Sequence is non-unique. Most records only contain one, but about 20% can have two or more records with the same Sequence. The INSERT app is a VB6 piece of crud throwing thousands insert commands at the table. The Inserted values are never in any particular order. So the Sequence of one insert may be 12345, and the next could be 12245. I know that this could cause SQL to move a lot of data to keep the clustered index in order. However, the Sequence of the inserts are generally close to being in order. All inserts would take place at the end of the clustered table. Eg: I have 5 million records with Sequence spanning 1 to 5 million. The INSERT app will be inserting sequence’s at the end of that range at any given time. Reordering of the data should be minimal (tens of thousands of records at most). Now, the UPDATE app is our .NET star. It does all UPDATES on the Sequence column. “Update Table_Docs Set Feild1=This, Field2=That…WHERE Sequence =12345” – hundreds of thousands of these a day. The UPDATES are completely and totally, random, touching all points of the table. All other processes are simply doing SELECT’s on this (Web pages). Regular indexes cover those. So my question is, what’s better….a unique clustered index on the ID column, benefiting the INSERT app, or a non-unique clustered index on the Sequence, benefiting the UPDATE app?

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• Strange issue with cout

  - by ben

  After reading from a text file, and storing it into a string, I tried to pass this message into another function that will print it out. This is what it looks like: http://imgur.com/MCjfRdp void insert (int id, string message){ cout << "Inserting " << message << " at" << endl; } Somehow the message behind the string overrides the message. But once I removed the " at" after message, it worked as expected. http://imgur.com/JdHPPmi void insert (int id, string message){ cout << "Inserting " << message << endl; } I somehow suspect the problem came from stringstream, but i couldn't find out where. Here's the code that read from file vector <string> line; fstream infile; string readLine, tempLine, action, tempLine1; int level, no; infile.open(fileName.c_str(),ios::in); int i = 0; while (!infile.eof()) { getline (infile, readLine); line.push_back(readLine); } infile.close(); line.pop_back(); for (int i = 0; i < line.size();i++) { stringstream ss (line.at(i)); getline (ss, action, ' '); if (action == "init") { // some other work here } else if (action == "insert") { tempLine = line.at(i); ss >> no; stringstream iline(tempLine); getline (iline, tempLine1, ' '); getline (iline, tempLine1, ' '); getline (iline, tempLine1, '\n'); Insert (no, tempLine1); } Since my file has different kinds of actions, here is what test.dat contains: insert 0 THIS IS A TEST edit: When i did file.txt, it came out as something like this. Inserting THIS IS A TEST at Inserting THIS IS TEST NO 2 at

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• Binary Search Tree Implementation

  - by Gabe

  I've searched the forum, and tried to implement the code in the threads I found. But I've been working on this real simple program since about 10am, and can't solve the seg. faults for the life of me. Any ideas on what I'm doing wrong would be greatly appreciated. BST.h (All the implementation problems should be in here.) #ifndef BST_H_ #define BST_H_ #include <stdexcept> #include <iostream> #include "btnode.h" using namespace std; /* A class to represent a templated binary search tree. */ template <typename T> class BST { private: //pointer to the root node in the tree BTNode<T>* root; public: //default constructor to make an empty tree BST(); /* You have to document these 4 functions */ void insert(T value); bool search(const T& value) const; bool search(BTNode<T>* node, const T& value) const; void printInOrder() const; void remove(const T& value); //function to print out a visual representation //of the tree (not just print the tree's values //on a single line) void print() const; private: //recursive helper function for "print()" void print(BTNode<T>* node,int depth) const; }; /* Default constructor to make an empty tree */ template <typename T> BST<T>::BST() { root = NULL; } template <typename T> void BST<T>::insert(T value) { BTNode<T>* newNode = new BTNode<T>(value); cout << newNode->data; if(root == NULL) { root = newNode; return; } BTNode<T>* current = new BTNode<T>(NULL); current = root; current->data = root->data; while(true) { if(current->left == NULL && current->right == NULL) break; if(current->right != NULL && current->left != NULL) { if(newNode->data > current->data) current = current->right; else if(newNode->data < current->data) current = current->left; } else if(current->right != NULL && current->left == NULL) { if(newNode->data < current->data) break; else if(newNode->data > current->data) current = current->right; } else if(current->right == NULL && current->left != NULL) { if(newNode->data > current->data) break; else if(newNode->data < current->data) current = current->left; } } if(current->data > newNode->data) current->left = newNode; else current->right = newNode; return; } //public helper function template <typename T> bool BST<T>::search(const T& value) const { return(search(root,value)); //start at the root } //recursive function template <typename T> bool BST<T>::search(BTNode<T>* node, const T& value) const { if(node == NULL || node->data == value) return(node != NULL); //found or couldn't find value else if(value < node->data) return search(node->left,value); //search left subtree else return search(node->right,value); //search right subtree } template <typename T> void BST<T>::printInOrder() const { //print out the value's in the tree in order // //You may need to use this function as a helper //and create a second recursive function //(see "print()" for an example) } template <typename T> void BST<T>::remove(const T& value) { if(root == NULL) { cout << "Tree is empty. No removal. "<<endl; return; } if(!search(value)) { cout << "Value is not in the tree. No removal." << endl; return; } BTNode<T>* current; BTNode<T>* parent; current = root; parent->left = NULL; parent->right = NULL; cout << root->left << "LEFT " << root->right << "RIGHT " << endl; cout << root->data << " ROOT" << endl; cout << current->data << "CURRENT BEFORE" << endl; while(current != NULL) { cout << "INTkhkjhbljkhblkjhlk " << endl; if(current->data == value) break; else if(value > current->data) { parent = current; current = current->right; } else { parent = current; current = current->left; } } cout << current->data << "CURRENT AFTER" << endl; // 3 cases : //We're looking at a leaf node if(current->left == NULL && current->right == NULL) // It's a leaf { if(parent->left == current) parent->left = NULL; else parent->right = NULL; delete current; cout << "The value " << value << " was removed." << endl; return; } // Node with single child if((current->left == NULL && current->right != NULL) || (current->left != NULL && current->right == NULL)) { if(current->left == NULL && current->right != NULL) { if(parent->left == current) { parent->left = current->right; cout << "The value " << value << " was removed." << endl; delete current; } else { parent->right = current->right; cout << "The value " << value << " was removed." << endl; delete current; } } else // left child present, no right child { if(parent->left == current) { parent->left = current->left; cout << "The value " << value << " was removed." << endl; delete current; } else { parent->right = current->left; cout << "The value " << value << " was removed." << endl; delete current; } } return; } //Node with 2 children - Replace node with smallest value in right subtree. if (current->left != NULL && current->right != NULL) { BTNode<T>* check; check = current->right; if((check->left == NULL) && (check->right == NULL)) { current = check; delete check; current->right = NULL; cout << "The value " << value << " was removed." << endl; } else // right child has children { //if the node's right child has a left child; Move all the way down left to locate smallest element if((current->right)->left != NULL) { BTNode<T>* leftCurrent; BTNode<T>* leftParent; leftParent = current->right; leftCurrent = (current->right)->left; while(leftCurrent->left != NULL) { leftParent = leftCurrent; leftCurrent = leftCurrent->left; } current->data = leftCurrent->data; delete leftCurrent; leftParent->left = NULL; cout << "The value " << value << " was removed." << endl; } else { BTNode<T>* temp; temp = current->right; current->data = temp->data; current->right = temp->right; delete temp; cout << "The value " << value << " was removed." << endl; } } return; } } /* Print out the values in the tree and their relationships visually. Sample output: 22 18 15 10 9 5 3 1 */ template <typename T> void BST<T>::print() const { print(root,0); } template <typename T> void BST<T>::print(BTNode<T>* node,int depth) const { if(node == NULL) { std::cout << std::endl; return; } print(node->right,depth+1); for(int i=0; i < depth; i++) { std::cout << "\t"; } std::cout << node->data << std::endl; print(node->left,depth+1); } #endif main.cpp #include "bst.h" #include <iostream> using namespace std; int main() { BST<int> tree; cout << endl << "LAB #13 - BINARY SEARCH TREE PROGRAM" << endl; cout << "----------------------------------------------------------" << endl; // Insert. cout << endl << "INSERT TESTS" << endl; // No duplicates allowed. tree.insert(0); tree.insert(5); tree.insert(15); tree.insert(25); tree.insert(20); // Search. cout << endl << "SEARCH TESTS" << endl; int x = 0; int y = 1; if(tree.search(x)) cout << "The value " << x << " is on the tree." << endl; else cout << "The value " << x << " is NOT on the tree." << endl; if(tree.search(y)) cout << "The value " << y << " is on the tree." << endl; else cout << "The value " << y << " is NOT on the tree." << endl; // Removal. cout << endl << "REMOVAL TESTS" << endl; tree.remove(0); tree.remove(1); tree.remove(20); // Print. cout << endl << "PRINTED DIAGRAM OF BINARY SEARCH TREE" << endl; cout << "----------------------------------------------------------" << endl; tree.print(); cout << endl << "Program terminated. Goodbye." << endl << endl; } BTNode.h #ifndef BTNODE_H_ #define BTNODE_H_ #include <iostream> /* A class to represent a node in a binary search tree. */ template <typename T> class BTNode { public: //constructor BTNode(T d); //the node's data value T data; //pointer to the node's left child BTNode<T>* left; //pointer to the node's right child BTNode<T>* right; }; /* Simple constructor. Sets the data value of the BTNode to "d" and defaults its left and right child pointers to NULL. */ template <typename T> BTNode<T>::BTNode(T d) : left(NULL), right(NULL) { data = d; } #endif Thanks.

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• Connection Reset on MySQL query

  - by sunwukung

  OK, I'm flummoxed.(i've asked this question over on Stack too - but I need to get it fixed so I'm asking here too - any help is GREATLY appreciated) I'm trying to execute a query on a database (locally) and I keep getting a connection reset error. I've been using the method below in a generic DAO class to build a query string and pass to Zend_Db API. public function insert($params) { $loop = false; $keys = $values = ''; foreach($params as $k => $v){ if($loop == true){ $keys .= ','; $values .= ','; } $keys .= $this->db->quoteIdentifier($k); $values .= $this->db->quote($v); $loop = true; } $sql = "INSERT INTO " . $this->table_name . " ($keys) VALUES ($values)"; //formatResult returns an array of info regarding the status and any result sets of the query //I've commented that method call out anyway, so I don't think it's that try { $this->db->query($sql); return $this->formatResult(array( true, 'New record inserted into: '.$this->table_name )); }catch(PDOException $e) { return $this->formatResult($e); } } So far, this has worked fine - the errors have been occurring since we generated new tables to record user input. The insert string looks like this: INSERT INTO tablename(`id`,`title`,`summary`,`description`,`keywords`,`type_id`,`categories`) VALUES ('5539','Sample Title','Sample content',' \'Lorem ipsum dolor sit amet, consectetur adipiscing elit. In et pellentesque mauris. Curabitur hendrerit, leo id ultrices pellentesque, est purus mattis ligula, vitae imperdiet neque ligula bibendum sapien. Curabitur aliquet nisi et odio pharetra tincidunt. Phasellus sed iaculis nisl. Fusce commodo mauris et purus vehicula dictum. Nulla feugiat molestie accumsan. Donec fermentum libero in risus tempus elementum aliquam et magna. Fusce vitae sem metus. Aenean commodo pharetra risus, nec pellentesque augue ullamcorper nec. Class aptent taciti sociosqu ad litora torquent per conubia nostra, per inceptos himenaeos. Nullam vel elit libero. Vestibulum in turpis nunc.\'','this,is,a,sample,array',1,'category title') Here are the parameters it's getting before assembling the query (var_dump): array 'id' => string '1' (length=4) 'title' => string 'Sample Title' (length=12) 'summary' => string 'Sample content' (length=14) 'description' => string '<p>'Lorem ipsum dolor sit amet, consectetur adipiscing elit. In et pellentesque mauris. Curabitur hendrerit, leo id ultrices pellentesque, est purus mattis ligula, vitae imperdiet neque ligula bibendum sapien. Curabitur aliquet nisi et odio pharetra tincidunt. Phasellus sed iaculis nisl. Fusce commodo mauris et purus vehicula dictum. Nulla feugiat molestie accumsan. Donec fermentum libero in risus tempus elementum aliquam et magna. Fusce vitae sem metus. Aenean commodo pharetra risus, nec pellentesque augue'... (length=677) 'keywords' => string 'this,is,a,sample,array' (length=22) 'type_id' => int 1 'categories' => string 'category title' (length=43) The next port of call was checking the limits on the table, since it seems to insert if the length of "description" is around the 300 mark (it varies between 310 - 330). The field limit is set to VARCHAR(1500) and the validation on this field won't allow anything past bigger than 1200 with HTML, 800 without. The real kicker is that if I take this sql string and execute it via the command line, it works fine - so I can't for the life of me figure out what's wrong. I've tried extending the server parameters i.e. http://stackoverflow.com/questions/1964554/unexpected-connection-reset-a-php-or-an-apache-issue So, in a nutshell, I'm stumped. Any ideas?

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• SQL SERVER – Update Statistics are Sampled By Default

  - by pinaldave

  After reading my earlier post SQL SERVER – Create Primary Key with Specific Name when Creating Table on Statistics, I have received another question by a blog reader. The question is as follows: Question: Are the statistics sampled by default? Answer: Yes. The sampling rate can be specified by the user and it can be anywhere between a very low value to 100%. Let us do a small experiment to verify if the auto update on statistics is left on. Also, let’s examine a very large table that is created and statistics by default- whether the statistics are sampled or not. USE [AdventureWorks] GO -- Create Table CREATE TABLE [dbo].[StatsTest]( [ID] [int] IDENTITY(1,1) NOT NULL, [FirstName] [varchar](100) NULL, [LastName] [varchar](100) NULL, [City] [varchar](100) NULL, CONSTRAINT [PK_StatsTest] PRIMARY KEY CLUSTERED ([ID] ASC) ) ON [PRIMARY] GO -- Insert 1 Million Rows INSERT INTO [dbo].[StatsTest] (FirstName,LastName,City) SELECT TOP 1000000 'Bob', CASE WHEN ROW_NUMBER() OVER (ORDER BY a.name)%2 = 1 THEN 'Smith' ELSE 'Brown' END, CASE WHEN ROW_NUMBER() OVER (ORDER BY a.name)%10 = 1 THEN 'New York' WHEN ROW_NUMBER() OVER (ORDER BY a.name)%10 = 5 THEN 'San Marino' WHEN ROW_NUMBER() OVER (ORDER BY a.name)%10 = 3 THEN 'Los Angeles' ELSE 'Houston' END FROM sys.all_objects a CROSS JOIN sys.all_objects b GO -- Update the statistics UPDATE STATISTICS [dbo].[StatsTest] GO -- Shows the statistics DBCC SHOW_STATISTICS ("StatsTest"PK_StatsTest) GO -- Clean up DROP TABLE [dbo].[StatsTest] GO Now let us observe the result of the DBCC SHOW_STATISTICS. The result shows that Resultset is for sure sampling for a large dataset. The percentage of sampling is based on data distribution as well as the kind of data in the table. Before dropping the table, let us check first the size of the table. The size of the table is 35 MB. Now, let us run the above code with lesser number of the rows. USE [AdventureWorks] GO -- Create Table CREATE TABLE [dbo].[StatsTest]( [ID] [int] IDENTITY(1,1) NOT NULL, [FirstName] [varchar](100) NULL, [LastName] [varchar](100) NULL, [City] [varchar](100) NULL, CONSTRAINT [PK_StatsTest] PRIMARY KEY CLUSTERED ([ID] ASC) ) ON [PRIMARY] GO -- Insert 1 Hundred Thousand Rows INSERT INTO [dbo].[StatsTest] (FirstName,LastName,City) SELECT TOP 100000 'Bob', CASE WHEN ROW_NUMBER() OVER (ORDER BY a.name)%2 = 1 THEN 'Smith' ELSE 'Brown' END, CASE WHEN ROW_NUMBER() OVER (ORDER BY a.name)%10 = 1 THEN 'New York' WHEN ROW_NUMBER() OVER (ORDER BY a.name)%10 = 5 THEN 'San Marino' WHEN ROW_NUMBER() OVER (ORDER BY a.name)%10 = 3 THEN 'Los Angeles' ELSE 'Houston' END FROM sys.all_objects a CROSS JOIN sys.all_objects b GO -- Update the statistics UPDATE STATISTICS [dbo].[StatsTest] GO -- Shows the statistics DBCC SHOW_STATISTICS ("StatsTest"PK_StatsTest) GO -- Clean up DROP TABLE [dbo].[StatsTest] GO You can see that Rows Sampled is just the same as Rows of the table. In this case, the sample rate is 100%. Before dropping the table, let us also check the size of the table. The size of the table is less than 4 MB. Let us compare the Result set just for a valid reference. Test 1: Total Rows: 1000000, Rows Sampled: 255420, Size of the Table: 35.516 MB Test 2: Total Rows: 100000, Rows Sampled: 100000, Size of the Table: 3.555 MB The reason behind the sample in the Test1 is that the data space is larger than 8 MB, and therefore it uses more than 1024 data pages. If the data space is smaller than 8 MB and uses less than 1024 data pages, then the sampling does not happen. Sampling aids in reducing excessive data scan; however, sometimes it reduces the accuracy of the data as well. Please note that this is just a sample test and there is no way it can be claimed as a benchmark test. The result can be dissimilar on different machines. There are lots of other information can be included when talking about this subject. I will write detail post covering all the subject very soon. Reference: Pinal Dave (http://blog.SQLAuthority.com) Filed under: Pinal Dave, SQL, SQL Authority, SQL Index, SQL Optimization, SQL Performance, SQL Query, SQL Scripts, SQL Server, SQL Tips and Tricks, T SQL, Technology Tagged: SQL Statistics

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• T-SQL Improvements And Data Types in ms sql 2008

  - by Aamir Hasan

   Microsoft SQL Server 2008 is a new version released in the first half of 2008 introducing new properties and capabilities to SQL Server product family. All these new and enhanced capabilities can be defined as the classic words like secure, reliable, scalable and manageable. SQL Server 2008 is secure. It is reliable. SQL2008 is scalable and is more manageable when compared to previous releases. Now we will have a look at the features that are making MS SQL Server 2008 more secure, more reliable, more scalable, etc. in details.Microsoft SQL Server 2008 provides T-SQL enhancements that improve performance and reliability. Itzik discusses composable DML, the ability to declare and initialize variables in the same statement, compound assignment operators, and more reliable object dependency information. Table-Valued ParametersInserts into structures with 1-N cardinality problematicOne order -> N order line items"N" is variable and can be largeDon't want to force a new order for every 20 line itemsOne database round-trip / line item slows things downNo ARRAY data type in SQL ServerXML composition/decomposition used as an alternativeTable-valued parameters solve this problemTable-Valued ParametersSQL Server has table variablesDECLARE @t TABLE (id int);SQL Server 2008 adds strongly typed table variablesCREATE TYPE mytab AS TABLE (id int);DECLARE @t mytab;Parameters must use strongly typed table variables Table Variables are Input OnlyDeclare and initialize TABLE variable  DECLARE @t mytab;  INSERT @t VALUES (1), (2), (3);  EXEC myproc @t;Procedure must declare variable READONLY  CREATE PROCEDURE usetable (    @t mytab READONLY ...)  AS    INSERT INTO lineitems SELECT * FROM @t;    UPDATE @t SET... -- no!T-SQL Syntax EnhancementsSingle statement declare and initialize  DECLARE @iint = 4;Compound Assignment Operators  SET @i += 1;Row constructors  DECLARE @t TABLE (id int, name varchar(20));  INSERT INTO @t VALUES    (1, 'Fred'), (2, 'Jim'), (3, 'Sue');Grouping SetsGrouping Sets allow multiple GROUP BY clauses in a single SQL statementMultiple, arbitrary, sets of subtotalsSingle read pass for performanceNested subtotals provide ever better performanceGrouping Sets are an ANSI-standardCOMPUTE BY is deprecatedGROUPING SETS, ROLLUP, CUBESQL Server 2008 - ANSI-syntax ROLLUP and CUBEPre-2008 non-ANSI syntax is deprecatedWITH ROLLUP produces n+1 different groupings of datawhere n is the number of columns in GROUP BYWITH CUBE produces 2^n different groupingswhere n is the number of columns in GROUP BYGROUPING SETS provide a "halfway measure"Just the number of different groupings you needGrouping Sets are visible in query planGROUPING_ID and GROUPINGGrouping Sets can produce non-homogeneous setsGrouping set includes NULL values for group membersNeed to distinguish by grouping and NULL valuesGROUPING (column expression) returns 0 or 1Is this a group based on column expr. or NULL value?GROUPING_ID (a,b,c) is a bitmaskGROUPING_ID bits are set based on column expressions a, b, and cMERGE StatementMultiple set operations in a single SQL statementUses multiple sets as inputMERGE target USING source ON ...Operations can be INSERT, UPDATE, DELETEOperations based onWHEN MATCHEDWHEN NOT MATCHED [BY TARGET] WHEN NOT MATCHED [BY SOURCE]More on MERGEMERGE statement can reference a $action columnUsed when MERGE used with OUTPUT clauseMultiple WHEN clauses possible For MATCHED and NOT MATCHED BY SOURCEOnly one WHEN clause for NOT MATCHED BY TARGETMERGE can be used with any table sourceA MERGE statement causes triggers to be fired onceRows affected includes total rows affected by all clausesMERGE PerformanceMERGE statement is transactionalNo explicit transaction requiredOne Pass Through TablesAt most a full outer joinMatching rows = when matchedLeft-outer join rows = when not matched by targetRight-outer join rows = when not matched by sourceMERGE and DeterminismUPDATE using a JOIN is non-deterministicIf more than one row in source matches ON clause, either/any row can be used for the UPDATEMERGE is deterministicIf more than one row in source matches ON clause, its an errorKeeping Track of DependenciesNew dependency views replace sp_dependsViews are kept in sync as changes occursys.dm_sql_referenced_entitiesLists all named entities that an object referencesExample: which objects does this stored procedure use?sys.dm_sql_referencing_entities 

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• Using the Katana Authentication handlers with NancyFx

  - by cibrax

  Once you write an OWIN Middleware service, it can be reused everywhere as long as OWIN is supported. In my last post, I discussed how you could write an Authentication Handler in Katana for Hawk (HMAC Authentication). Good news is NancyFx can be run as an OWIN handler, so you can use many of existing middleware services, including the ones that are ship with Katana. Running NancyFx as a OWIN handler is pretty straightforward, and discussed in detail as part of the NancyFx documentation here. After run the steps described there and you have the application working, only a few more steps are required to register the additional middleware services. The example bellow shows how the Startup class is modified to include Hawk authentication. public class Startup { public void Configuration(IAppBuilder app) { app.UseHawkAuthentication(new HawkAuthenticationOptions { Credentials = (id) => { return new HawkCredential { Id = "dh37fgj492je", Key = "werxhqb98rpaxn39848xrunpaw3489ruxnpa98w4rxn", Algorithm = "hmacsha256", User = "steve" }; } }); app.UseNancy(); } } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } This code registers the Hawk Authentication Handler on top of the OWIN pipeline, so it will try to authenticate the calls before the request messages are passed over to NancyFx. The authentication handlers in Katana set the user principal in the OWIN environment using the key “server.User”. The following code shows how you can get that principal in a NancyFx module, public class HomeModule : NancyModule { public HomeModule() { Get["/"] = x => { var env = (IDictionary<string, object>)Context.Items[NancyOwinHost.RequestEnvironmentKey]; if (!env.ContainsKey("server.User") || env["server.User"] == null) { return HttpStatusCode.Unauthorized; } var identity = (ClaimsPrincipal)env["server.User"]; return "Hello " + identity.Identity.Name; }; } } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } Thanks to OWIN, you don’t know any details of how these cross cutting concerns can be implemented in every possible web application framework.

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• Linq To SQL: Behaviour for table field which is NotNull and having Default value or binding

  - by kaushalparik27

  I found this something interesting while wandering over community which I would like to share. The post is whole about: DBML is not considering the table field's "Default value or Binding" setting which is a NotNull. I mean the field which can not be null but having default value set needs to be set IsDbGenerated = true in DBML file explicitly.Consider this situation: There is a simple tblEmployee table with below structure: The fields are simple. EmployeeID is a Primary Key with Identity Specification = True with Identity Seed = 1 to autogenerate numeric value for this field. EmployeeName and their EmailAddress to store in rest of 2 fields. And the last one is "DateAdded" with DateTime datatype which doesn't allow NULL but having Default Value/Binding with "GetDate()". That means if we don't pass any value to this field then SQL will insert current date in "DateAdded" field.So, I start with a new website, add a DBML file and dropped the said table to generate LINQ To SQL context class. Finally, I write a simple code snippet to insert data into the tblEmployee table; BUT, I am not passing any value to "DateAdded" field. Because I am considering SQL Server's "Default Value or Binding (GetDate())" setting to this field and understand that SQL will insert current date to this field.        using (TestDatabaseDataContext context = new TestDatabaseDataContext())        {            tblEmployee tblEmpObjet = new tblEmployee();            tblEmpObjet.EmployeeName = "KaushaL";            tblEmpObjet.EmployeeEmailAddress = "[email protected]";            context.tblEmployees.InsertOnSubmit(tblEmpObjet);            context.SubmitChanges();        }Here comes the twist when application give me below error:  This is something not expecting! From the error it clearly depicts that LINQ is passing NULL value to "DateAdded" Field while according to my understanding it should respect Sql Server's "Default value or Binding" setting for this field. A bit googling and I found very interesting related to this problem.When we set Primary Key to any field with "Identity Specification" Property set to true; DBML set one important property "IsDbGenerated=true" for this field. BUT, when we set "Default Value or Biding" property for some field; we need to explicitly tell the DBML/LINQ to let it know that this field is having default binding at DB side that needs to be respected if I don't pass any value. So, the solution is: You need to explicitly set "IsDbGenerated=true" for such field to tell the LINQ that the field is having default value or binding at Sql Server side so, please don't worry if i don't pass any value for it.You can select the field and set this property from property window in DBML Designer file or write the property in DBML.Designer.cs file directly. I have attached a working example with required table script with this post here. I hope this would be helpful for someone hunting for the same. Happy Discovery!

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• SQL SERVER – UNION ALL and ORDER BY – How to Order Table Separately While Using UNION ALL

  - by pinaldave

  I often see developers trying following syntax while using ORDER BY. SELECT Columns FROM TABLE1 ORDER BY Columns UNION ALL SELECT Columns FROM TABLE2 ORDER BY Columns However the above query will return following error. Msg 156, Level 15, State 1, Line 5 Incorrect syntax near the keyword ‘ORDER’. It is not possible to use two different ORDER BY in the UNION statement. UNION returns single resultsetand as per the Logical Query Processing Phases. However, if your requirement is such that you want your top and bottom query of the UNION resultset independently sorted but in the same resultset you can add an additional static column and order by that column. Let us re-create the same scenario. First create two tables and populated with sample data. USE tempdb GO -- Create table CREATE TABLE t1 (ID INT, Col1 VARCHAR(100)); CREATE TABLE t2 (ID INT, Col1 VARCHAR(100)); GO -- Sample Data Build INSERT INTO t1 (ID, Col1) SELECT 1, 'Col1-t1' UNION ALL SELECT 2, 'Col2-t1' UNION ALL SELECT 3, 'Col3-t1'; INSERT INTO t2 (ID, Col1) SELECT 3, 'Col1-t2' UNION ALL SELECT 2, 'Col2-t2' UNION ALL SELECT 1, 'Col3-t2'; GO If we SELECT the data from both the table using UNION ALL . -- SELECT without ORDER BY SELECT ID, Col1 FROM t1 UNION ALL SELECT ID, Col1 FROM t2 GO We will get the data in following order. However, our requirement is to get data in following order. If we need data ordered by Column1 we can ORDER the resultset ordered by Column1. -- SELECT with ORDER BY SELECT ID, Col1 FROM t1 UNION ALL SELECT ID, Col1 FROM t2 ORDER BY ID GO Now to get the data in independently sorted in UNION ALL let us add additional column OrderKey and use ORDER BY  on that column. I think the description does not do proper justice let us see the example here. -- SELECT with ORDER BY - with ORDER KEY SELECT ID, Col1, 'id1' OrderKey FROM t1 UNION ALL SELECT ID, Col1, 'id2' OrderKey FROM t2 ORDER BY OrderKey, ID GO The above query will give the desired result. Now do not forget to clean up the database by running the following script. -- Clean up DROP TABLE t1; DROP TABLE t2; GO Here is the complete script used in this example. USE tempdb GO -- Create table CREATE TABLE t1 (ID INT, Col1 VARCHAR(100)); CREATE TABLE t2 (ID INT, Col1 VARCHAR(100)); GO -- Sample Data Build INSERT INTO t1 (ID, Col1) SELECT 1, 'Col1-t1' UNION ALL SELECT 2, 'Col2-t1' UNION ALL SELECT 3, 'Col3-t1'; INSERT INTO t2 (ID, Col1) SELECT 3, 'Col1-t2' UNION ALL SELECT 2, 'Col2-t2' UNION ALL SELECT 1, 'Col3-t2'; GO -- SELECT without ORDER BY SELECT ID, Col1 FROM t1 UNION ALL SELECT ID, Col1 FROM t2 GO -- SELECT with ORDER BY SELECT ID, Col1 FROM t1 UNION ALL SELECT ID, Col1 FROM t2 ORDER BY ID GO -- SELECT with ORDER BY - with ORDER KEY SELECT ID, Col1, 'id1' OrderKey FROM t1 UNION ALL SELECT ID, Col1, 'id2' OrderKey FROM t2 ORDER BY OrderKey, ID GO -- Clean up DROP TABLE t1; DROP TABLE t2; GO I am sure there are many more ways to achieve this, what method would you use if you have to face the similar situation? Reference: Pinal Dave (http://blog.sqlauthority.com)   Filed under: Best Practices, PostADay, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, T SQL, Technology

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• Securing Flexfield Value Sets in EBS 12.2

  - by Sara Woodhull

  Release 12.2 includes a new feature: flexfield value set security. This new feature gives you additional options for ensuring that different administrators have non-overlapping responsibilities, which in turn provides checks and balances for sensitive activities.  Separation of Duties (SoD) is one of the key concepts of internal controls and is a requirement for many regulations including: Sarbanes-Oxley (SOX) Act Health Insurance Portability and Accountability Act (HIPAA) European Union Data Protection Directive. Its primary intent is to put barriers in place to prevent fraud or theft by an individual acting alone. Implementing Separation of Duties requires minimizing the possibility that users could modify data across application functions where the users should not normally have access. For flexfields and report parameters in Oracle E-Business Suite, values in value sets can affect functionality such as the rollup of accounting data, job grades used at a company, and so on. Controlling access to the creation or modification of value set values can be an important piece of implementing Separation of Duties in an organization. New Flexfield Value Set Security feature Flexfield value set security allows system administrators to restrict users from viewing, adding or updating values in specific value sets. Value set security enables role-based separation of duties for key flexfields, descriptive flexfields, and report parameters. For example, you can set up value set security such that certain users can view or insert values for any value set used by the Accounting Flexfield but no other value sets, while other users can view and update values for value sets used for any flexfields in Oracle HRMS. You can also segregate access by Operating Unit as well as by role or responsibility.Value set security uses a combination of data security and role-based access control in Oracle User Management. Flexfield value set security provides a level of security that is different from the previously-existing and similarly-named features in Oracle E-Business Suite: Function security controls whether a user has access to a specific page or form, as well as what operations the user can do in that screen. Flexfield value security controls what values a user can enter into a flexfield segment or report parameter (by responsibility) during routine data entry in many transaction screens across Oracle E-Business Suite. Flexfield value set security (this feature, new in Release 12.2) controls who can view, insert, or update values for a particular value set (by flexfield, report, or value set) in the Segment Values form (FNDFFMSV). The effect of flexfield value set security is that a user of the Segment Values form will only be able to view those value sets for which the user has been granted access. Further, the user will be able to insert or update/disable values in that value set if the user has been granted privileges to do so.  Flexfield value set security affects independent, dependent, and certain table-validated value sets for flexfields and report parameters. Initial State of the Feature upon Upgrade Because this is a new security feature, it is turned on by default.  When you initially install or upgrade to Release 12.2.2, no users are allowed to view, insert or update any value set values (users may even think that their values are missing or invalid because they cannot see the values).  You must explicitly set up access for specific users by enabling appropriate grants and roles for those users.We recommend using flexfield value set security as part of a comprehensive Separation of Duties strategy. However, if you choose not to implement flexfield value set security upon upgrading to or installing Release 12.2, you can enable backwards compatibility--users can access any value sets if they have access to the Values form--after you upgrade. The feature does not affect day-to-day transactions that use flexfields.  However, you must either set up specific grants and roles or enable backwards compatibility before users can create new values or update or disable existing values. For more information, see: Release 12.2 Flexfield Value Set Security Documentation Update for Patch 17305947:R12.FND.C (Document 1589204.1) R12.2 TOI: Implement and Use Application Object Library (AOL) - Flexfields Security and Separation of Duties for Value Sets (recorded training)

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• Replacing ASP.NET Forms Authentication with WIF Session Authentication (for the better)

  - by Your DisplayName here!

  ASP.NET Forms Authentication and WIF Session Authentication (which has *nothing* to do with ASP.NET sessions) are very similar. Both inspect incoming requests for a special cookie that contains identity information, if that cookie is present it gets validated and if that is successful, the identity information is made available to the application via HttpContext.User/Thread.CurrentPrincipal. The main difference between the two is the identity to cookie serialization engine that sits below. Whereas ForsmAuth can only store the name of the user and an additional UserData string. It is limited to a single cookie and hardcoded to protection via the machine key. WIF session authentication in turn has these additional features: Can serialize a complete ClaimsPrincipal (including claims) to the cookie(s). Has a cookie overflow mechanism when data gets too big. In total it can create up to 8 cookies (á 4 KB) per domain (not that I would recommend round tripping that much data). Supports server side caching (which is an extensible mechanism). Has an extensible mechanism for protection (DPAPI by default, RSA as an option for web farms, and machine key based protection is coming in .NET 4.5) So in other words – session authentication is the superior technology, and if done cleverly enough you can replace FormsAuth without any changes to your application code. The only features missing is the redirect mechanism to a login page and an easy to use API to set authentication cookies. But that’s easy to add ;) FormsSessionAuthenticationModule This module is a sub class of the standard WIF session module, adding the following features: Handling EndRequest to do the redirect on 401s to the login page configured for FormsAuth. Reads the FormsAuth cookie name, cookie domain, timeout and require SSL settings to configure the module accordingly. Implements sliding expiration if configured for FormsAuth. It also uses the same algorithm as FormsAuth to calculate when the cookie needs renewal. Implements caching of the principal on the server side (aka session mode) if configured in an AppSetting. Supports claims transformation via a ClaimsAuthenticationManager. As you can see, the whole module is designed to easily replace the FormsAuth mechanism. Simply set the authentication mode to None and register the module. In the spirit of the FormsAuthentication class, there is also now a SessionAuthentication class with the same methods and signatures (e.g. SetAuthCookie and SignOut). The rest of your application code should not be affected. In addition the session module looks for a HttpContext item called “NoRedirect”. If that exists, the redirect to the login page will *not* happen, instead the 401 is passed back to the client. Very useful if you are implementing services or web APIs where you want the actual status code to be preserved. A corresponding UnauthorizedResult is provided that gives you easy access to the context item. The download contains a sample app, the module and an inspector for session cookies and tokens. Let’s hope that in .NET 4.5 such a module comes out of the box. HTH

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• Windows Azure Recipe: Social Web / Big Media

  - by Clint Edmonson

  With the rise of social media there’s been an explosion of special interest media web sites on the web. From athletics to board games to funny animal behaviors, you can bet there’s a group of people somewhere on the web talking about it. Social media sites allow us to interact, share experiences, and bond with like minded enthusiasts around the globe. And through the power of software, we can follow trends in these unique domains in real time. Drivers Reach Scalability Media hosting Global distribution Solution Here’s a sketch of how a social media application might be built out on Windows Azure: Ingredients Traffic Manager (optional) – can be used to provide hosting and load balancing across different instances and/or data centers. Perfect if the solution needs to be delivered to different cultures or regions around the world. Access Control – this service is essential to managing user identity. It’s backed by a full blown implementation of Active Directory and allows the definition and management of users, groups, and roles. A pre-built ASP.NET membership provider is included in the training kit to leverage this capability but it’s also flexible enough to be combined with external Identity providers including Windows LiveID, Google, Yahoo!, and Facebook. The provider model has extensibility points to hook into other identity providers as well. Web Role – hosts the core of the web application and presents a central social hub users. Database – used to store core operational, functional, and workflow data for the solution’s web services. Caching (optional) – as a web site traffic grows caching can be leveraged to keep frequently used read-only, user specific, and application resource data in a high-speed distributed in-memory for faster response times and ultimately higher scalability without spinning up more web and worker roles. It includes a token based security model that works alongside the Access Control service. Tables (optional) – for semi-structured data streams that don’t need relational integrity such as conversations, comments, or activity streams, tables provide a faster and more flexible way to store this kind of historical data. Blobs (optional) – users may be creating or uploading large volumes of heterogeneous data such as documents or rich media. Blob storage provides a scalable, resilient way to store terabytes of user data. The storage facilities can also integrate with the Access Control service to ensure users’ data is delivered securely. Content Delivery Network (CDN) (optional) – for sites that service users around the globe, the CDN is an extension to blob storage that, when enabled, will automatically cache frequently accessed blobs and static site content at edge data centers around the world. The data can be delivered statically or streamed in the case of rich media content. Training These links point to online Windows Azure training labs and resources where you can learn more about the individual ingredients described above. (Note: The entire Windows Azure Training Kit can also be downloaded for offline use.) Windows Azure (16 labs) Windows Azure is an internet-scale cloud computing and services platform hosted in Microsoft data centers, which provides an operating system and a set of developer services which can be used individually or together. It gives developers the choice to build web applications; applications running on connected devices, PCs, or servers; or hybrid solutions offering the best of both worlds. New or enhanced applications can be built using existing skills with the Visual Studio development environment and the .NET Framework. With its standards-based and interoperable approach, the services platform supports multiple internet protocols, including HTTP, REST, SOAP, and plain XML SQL Azure (7 labs) Microsoft SQL Azure delivers on the Microsoft Data Platform vision of extending the SQL Server capabilities to the cloud as web-based services, enabling you to store structured, semi-structured, and unstructured data. Windows Azure Services (9 labs) As applications collaborate across organizational boundaries, ensuring secure transactions across disparate security domains is crucial but difficult to implement. Windows Azure Services provides hosted authentication and access control using powerful, secure, standards-based infrastructure. See my Windows Azure Resource Guide for more guidance on how to get started, including links web portals, training kits, samples, and blogs related to Windows Azure.

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• ArchBeat Link-o-Rama Top 10 for September 9-15, 2012

  - by Bob Rhubart

  The Top 10 most-viewed items shared on the OTN ArchBeat Facebook page for the week of September 9-15, 2017. 15 Lessons from 15 Years as a Software Architect | Ingo Rammer In this presentation from the GOTO Conference in Copenhagen, Ingo Rammer shares 15 tips regarding people, complexity and technology that he learned doing software architecture for 15 years. Attend OTN Architect Day – by Architects, for Architects – October 25 You won't need 3D glasses to take in these live presentations (8 sessions, two tracks) on Cloud computing, SOA, and engineered systems. And the ticket price is: Zero. Nothing. Absolutely free. Register now for Oracle Technology Network Architect Day in Los Angeles. Thursday October 25, 2012, 8:00 a.m. – 5:00 p.m. Sofitel Los Angeles , 8555 Beverly Boulevard , Los Angeles, CA 90048. Cloud API and service designers, stop thinking small | Cloud Computing - InfoWorld "The focus must shift away from fine-grained APIs that provide some type of primitive service, such as pushing data to a block of storage or perhaps making a request to a cloud-rooted database," says InfoWorld's David Linthicum. "To go beyond primitives, you must understand how these services should be used in a much larger architectural context. In other words, you need to understand how businesses will employ these services to form real workplace solutions—inside and outside the enterprise." Adding a runtime picker to a taskflow parameter in WebCenter | Yannick Ongena Oracle ACE Yannick Ongena shows how to create an Oracle WebCenter popup to allow users to "select items or do more complex things." Oracle IAM 11g R2 docs are now available "One of the great things about the new doc set is the inclusion of ePub files," says Fusion Middleware A-Team blogger Chris Johnson. "This means that if you have an iPad you can load up the doc library onto that and read the docs on the couch." Setting up a local Yum Server using the Exalogic ZFS Storage Appliance | Donald A concise technical post from the man named Donald. What's New in Oracle VM VirtualBox 4.2? | The Fat Bloke Sings "One of the trends we've seen is that as the average host platform becomes more powerful, our users are consistently running more and more vm's," says The Fat Bloke. "Some of our users have large libraries of vm's of various vintages, whilst others have groups of vm's that are run together as an assembly of the various tiers in a multi-tiered software solution, for example, a database tier, middleware tier, and front-ends." The new VirtualBox release, a year in the making, addresses the needs of these users, he explains. Configuring Oracle Business Intelligence 11g MDS XML Source Control Management with Git Version Control | Christian Screen Oracle ACE Christian Screen developed this tutorial for those interested in learning how to configure the Oracle Business Intelligence 11g (11.1.1.6) metadata repository for development using the new MDS XML source control management functionality. Identity and Access Management at Oracle Open World 2012 | Brian Eidelman Fusion Middleware A-Team blogger Brian Eideleman highlights three Oracle Openworld sessions that will put Identity and Access Management in the spotlight, and shares a link to the "Focus On: Identity Management" document, a comprehensive listing of Openworld activities also dealing with IM. Starting and stopping WebLogic automatically using Upstart | Chris Johnson "In Ubuntu, RedHat and Oracle Linux there's a new flavor of init called Upstart that all the kids are using," says Oracle Fusion Middleware A-Team member Chris Johnson. "It's the new hotness when it comes to making programs into daemons and wiring them to start and stop at appropriate times." Thought for the Day "The purpose of software engineering is to control complexity, not to create it." — Pamela Zave Source: SoftwareQuotes.com

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• ArchBeat Link-o-Rama for 2012-06-29

  - by Bob Rhubart

  Backward-compatible vs. forward-compatible: a tale of two clouds | William Vambenepe "There is the Cloud that provides value by requiring as few changes as possible. And there is the Cloud that provides value by raising the abstraction and operation level," says William Vambenepe. "The backward-compatible Cloud versus the forward-compatible Cloud." Vambenepe was a panelist on the recent ArchBeat podcast Public, Private, and Hybrid Clouds. Andrejus Baranovskis's Blog: ADF 11g PS5 Application with Customized BPM Worklist Task Flow (MDS Seeded Customization) Oracle ACE Director Andrejus Baranovskis investigates "how you can customize a standard BPM Task Flow through MDS Seeded customization." Oracle OpenWorld 2012 Music Festival If, after a day spent in sessions at Oracle Openworld, you want nothing more than to head back to your hotel for a quiet evening spent responding to email, please ignore the rest of this message. Because every night from Sept 30 to Oct 4 the streets of San Francisco will pulsate with music from a vast array of bands representing more musical styles than a single human brain an comprehend. It's the first ever Oracle Music Festival, baby, 7:00pm to 1:00am every night. Are those emails that important...? Resource Kit: Oracle Exadata - includes demos, videos, product datasheets, and technical white papers. This free resource kit includes several customer case study videos, two 3D product demos, several product datasheets, and three technical architecture white papers. Registration is required for the who don't already have a free Oracle.com membership account. Some execs contemplate making 'Bring Your Own Device' mandatory | ZDNet "Companies and agencies are recognizing that individual employees are doing a better job of handling and managing their devices than their harried and overworked IT departments – who need to focus on bigger priorities, such as analytics and cloud," says ZDNet SOA blogger Joe McKendrick. Podcast Show Notes: Public, Private, and Hybrid Clouds All three parts of this discussion are now available. Featuring a panel of leading Oracle cloud computing experts, including Dr. James Baty, Mark T. Nelson, Ajay Srivastava, and William Vambenepe, the discussion covers an overview of the various flavors of cloud computing, the importance of standards, Why cloud computing is a paradigm shift—and why it isn't, and advice on what architects need to know to take advantage of the cloud. And for those who prefer reading to listening, a complete transcript is also available. Amazon AMIs and Oracle VM templates (Cloud Migrations) Cloud migration expert Tom Laszewski shares an objective comparison of these two resources. IOUC : Blogs : Read the latest news on the global user group community - June 2012! The June 2012 edition of "Are You a Member Yet?"—the quarterly newsletter about Oracle user group communities around the world. Webcast: Introducing Identity Management 11g R2 - July 19 Date: Thursday, July 19, 2012 Time: 10am PT / 1pm ET Please join Oracle and customer executives for the launch of Oracle Identity Management 11g R2, the breakthrough technology that dramatically expands the reach of identity management to cloud and mobile environments. Thought for the Day "The most important single aspect of software development is to be clear about what you are trying to build." — Bjarne Stroustrup Source: SoftwareQuotes.com

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• Stale statistics on a newly created temporary table in a stored procedure can lead to poor performance

  - by sqlworkshops

  When you create a temporary table you expect a new table with no past history (statistics based on past existence), this is not true if you have less than 6 updates to the temporary table. This might lead to poor performance of queries which are sensitive to the content of temporary tables.I was optimizing SQL Server Performance at one of my customers who provides search functionality on their website. They use stored procedure with temporary table for the search. The performance of the search depended on who searched what in the past, option (recompile) by itself had no effect. Sometimes a simple search led to timeout because of non-optimal plan usage due to this behavior. This is not a plan caching issue rather temporary table statistics caching issue, which was part of the temporary object caching feature that was introduced in SQL Server 2005 and is also present in SQL Server 2008 and SQL Server 2012. In this customer case we implemented a workaround to avoid this issue (see below for example for workarounds).When temporary tables are cached, the statistics are not newly created rather cached from the past and updated based on automatic update statistics threshold. Caching temporary tables/objects is good for performance, but caching stale statistics from the past is not optimal.We can work around this issue by disabling temporary table caching by explicitly executing a DDL statement on the temporary table. One possibility is to execute an alter table statement, but this can lead to duplicate constraint name error on concurrent stored procedure execution. The other way to work around this is to create an index.I think there might be many customers in such a situation without knowing that stale statistics are being cached along with temporary table leading to poor performance.Ideal solution is to have more aggressive statistics update when the temporary table has less number of rows when temporary table caching is used. I will open a connect item to report this issue.Meanwhile you can mitigate the issue by creating an index on the temporary table. You can monitor active temporary tables using Windows Server Performance Monitor counter: SQL Server: General Statistics->Active Temp Tables. The script to understand the issue and the workaround is listed below:set nocount onset statistics time offset statistics io offdrop table tab7gocreate table tab7 (c1 int primary key clustered, c2 int, c3 char(200))gocreate index test on tab7(c2, c1, c3)gobegin trandeclare @i intset @i = 1while @i <= 50000begininsert into tab7 values (@i, 1, ‘a’)set @i = @i + 1endcommit trangoinsert into tab7 values (50001, 1, ‘a’)gocheckpointgodrop proc test_slowgocreate proc test_slow @i intasbegindeclare @j intcreate table #temp1 (c1 int primary key)insert into #temp1 (c1) select @iselect @j = t7.c1 from tab7 t7 inner join #temp1 t on (t7.c2 = t.c1)endgodbcc dropcleanbuffersset statistics time onset statistics io ongo–high reads as expected for parameter ’1'exec test_slow 1godbcc dropcleanbuffersgo–high reads that are not expected for parameter ’2'exec test_slow 2godrop proc test_with_recompilegocreate proc test_with_recompile @i intasbegindeclare @j intcreate table #temp1 (c1 int primary key)insert into #temp1 (c1) select @iselect @j = t7.c1 from tab7 t7 inner join #temp1 t on (t7.c2 = t.c1)option (recompile)endgodbcc dropcleanbuffersset statistics time onset statistics io ongo–high reads as expected for parameter ’1'exec test_with_recompile 1godbcc dropcleanbuffersgo–high reads that are not expected for parameter ’2'–low reads on 3rd execution as expected for parameter ’2'exec test_with_recompile 2godrop proc test_with_alter_table_recompilegocreate proc test_with_alter_table_recompile @i intasbegindeclare @j intcreate table #temp1 (c1 int primary key)–to avoid caching of temporary tables one can create a constraint–but this might lead to duplicate constraint name error on concurrent usagealter table #temp1 add constraint test123 unique(c1)insert into #temp1 (c1) select @iselect @j = t7.c1 from tab7 t7 inner join #temp1 t on (t7.c2 = t.c1)option (recompile)endgodbcc dropcleanbuffersset statistics time onset statistics io ongo–high reads as expected for parameter ’1'exec test_with_alter_table_recompile 1godbcc dropcleanbuffersgo–low reads as expected for parameter ’2'exec test_with_alter_table_recompile 2godrop proc test_with_index_recompilegocreate proc test_with_index_recompile @i intasbegindeclare @j intcreate table #temp1 (c1 int primary key)–to avoid caching of temporary tables one can create an indexcreate index test on #temp1(c1)insert into #temp1 (c1) select @iselect @j = t7.c1 from tab7 t7 inner join #temp1 t on (t7.c2 = t.c1)option (recompile)endgoset statistics time onset statistics io ondbcc dropcleanbuffersgo–high reads as expected for parameter ’1'exec test_with_index_recompile 1godbcc dropcleanbuffersgo–low reads as expected for parameter ’2'exec test_with_index_recompile 2go

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• Improving the efficiency of frustum culling

  - by DeadMG

  I've got some code which performs frustum culling. However, this defines the "frustum" way too broadly- when I have ~10 objects on screen, the code returns 42 objects to be rendered. I've tried taking "slices" through the frustum to attempt to increase the accuracy of the technique, but it doesn't seem to have made much impact. I also significantly reduced the far plane, so that the objects are barely at the edge. Here's my code (where size is the size in screen space- the resolution of the client area of the window I'm rendering into). Any suggestions? auto&& size = GetDimensions(); D3DVIEWPORT9 vp = { 0, 0, size.x, size.y, 0, 1 }; D3DCALL(device->SetViewport(&vp)); static const int slices = 10; std::vector<Object*> result; for(int i = 0; i < slices; i++) { D3DXVECTOR3 WorldSpaceFrustrumPoints[8] = { D3DXVECTOR3(0, size.y, static_cast<float>(i) / slices), D3DXVECTOR3(size.x, 0, static_cast<float>(i) / slices), D3DXVECTOR3(size.x, size.y, static_cast<float>(i) / slices), D3DXVECTOR3(0, 0, static_cast<float>(i) / slices), D3DXVECTOR3(0, 0, static_cast<float>(i + 1) / slices), D3DXVECTOR3(size.x, 0, static_cast<float>(i + 1) / slices), D3DXVECTOR3(size.x, size.y, static_cast<float>(i + 1) / slices), D3DXVECTOR3(0, size.y, static_cast<float>(i + 1) / slices) }; D3DXMATRIXA16 Identity; D3DXMatrixIdentity(&Identity); D3DXVec3UnprojectArray( WorldSpaceFrustrumPoints, sizeof(D3DXVECTOR3), WorldSpaceFrustrumPoints, sizeof(D3DXVECTOR3), &vp, &Projection, &View, &Identity, 8 ); Math::AABB Frustrum; auto world_begin = std::begin(WorldSpaceFrustrumPoints); auto world_end = std::end(WorldSpaceFrustrumPoints); auto world_initial = WorldSpaceFrustrumPoints[0]; Frustrum.BottomLeftClosest.x = std::accumulate(world_begin, world_end, world_initial, [](D3DXVECTOR3 lhs, D3DXVECTOR3 rhs) { return lhs.x < rhs.x ? lhs : rhs; }).x; Frustrum.BottomLeftClosest.y = std::accumulate(world_begin, world_end, world_initial, [](D3DXVECTOR3 lhs, D3DXVECTOR3 rhs) { return lhs.y < rhs.y ? lhs : rhs; }).y; Frustrum.BottomLeftClosest.z = std::accumulate(world_begin, world_end, world_initial, [](D3DXVECTOR3 lhs, D3DXVECTOR3 rhs) { return lhs.z < rhs.z ? lhs : rhs; }).z; Frustrum.TopRightFurthest.x = std::accumulate(world_begin, world_end, world_initial, [](D3DXVECTOR3 lhs, D3DXVECTOR3 rhs) { return lhs.x > rhs.x ? lhs : rhs; }).x; Frustrum.TopRightFurthest.y = std::accumulate(world_begin, world_end, world_initial, [](D3DXVECTOR3 lhs, D3DXVECTOR3 rhs) { return lhs.y > rhs.y ? lhs : rhs; }).y; Frustrum.TopRightFurthest.z = std::accumulate(world_begin, world_end, world_initial, [](D3DXVECTOR3 lhs, D3DXVECTOR3 rhs) { return lhs.z > rhs.z ? lhs : rhs; }).z; auto slices_result = ObjectTree.collision(Frustrum); result.insert(result.end(), slices_result.begin(), slices_result.end()); } return result;

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• Windows Phone 7 and WS-Trust

  - by Your DisplayName here!

  A question that I often hear these days is: “Can I connect a Windows Phone 7 device to my existing enterprise services?”. Well – since most of my services are typically issued token based, this requires support for WS-Trust and WS-Security on the client. Let’s see what’s necessary to write a WP7 client for this scenario. First I converted the Silverlight library that comes with the Identity Training Kit to WP7. Some things are not supported in WP7 WCF (like message inspectors and some client runtime hooks) – but besides that this was a simple copy+paste job. Very nice! Next I used the WSTrustClient to request tokens from my STS: private WSTrustClient GetWSTrustClient() {     var client = new WSTrustClient(         new WSTrustBindingUsernameMixed(),         new EndpointAddress("https://identity.thinktecture.com/…/issue.svc/mixed/username"),         new UsernameCredentials(_txtUserName.Text, _txtPassword.Password));     return client; } private void _btnLogin_Click(object sender, RoutedEventArgs e) {     _client = GetWSTrustClient();       var rst = new RequestSecurityToken(WSTrust13Constants.KeyTypes.Bearer)     {         AppliesTo = new EndpointAddress("https://identity.thinktecture.com/rp/")     };       _client.IssueCompleted += client_IssueCompleted;     _client.IssueAsync(rst); } I then used the returned RSTR to talk to the WCF service. Due to a bug in the combination of the Silverlight library and the WP7 runtime – symmetric key tokens seem to have issues currently. Bearer tokens work fine. So I created the following binding for the WCF endpoint specifically for WP7. <customBinding>   <binding name="mixedNoSessionBearerBinary">     <security authenticationMode="IssuedTokenOverTransport"               messageSecurityVersion="WSSecurity11 WSTrust13 WSSecureConversation13 WSSecurityPolicy12 BasicSecurityProfile10">       <issuedTokenParameters keyType="BearerKey" />     </security>     <binaryMessageEncoding />     <httpsTransport/>   </binding> </customBinding> The binary encoding is not necessary, but will speed things up a little for mobile devices. I then call the service with the following code: private void _btnCallService_Click(object sender, RoutedEventArgs e) {     var binding = new CustomBinding(         new BinaryMessageEncodingBindingElement(),         new HttpsTransportBindingElement());       _proxy = new StarterServiceContractClient(         binding,         new EndpointAddress("…"));     using (var scope = new OperationContextScope(_proxy.InnerChannel))     {         OperationContext.Current.OutgoingMessageHeaders.Add(new IssuedTokenHeader(Globals.RSTR));         _proxy.GetClaimsAsync();     } } works. download

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• How to properly test for constraint violation in hibernate?

  - by Cesar

  I'm trying to test Hibernate mappings, specifically a unique constraint. My POJO is mapped as follows: <property name="name" type="string" unique="true" not-null="true" /> What I want to do is to test that I can't persist two entities with the same name: @Test(expected=ConstraintViolationException.class) public void testPersistTwoExpertiseAreasWithTheSameNameIsNotAllowed(){ ExpertiseArea ea = new ExpertiseArea("Design"); ExpertiseArea otherEA = new ExpertiseArea("Design"); ead.setSession(getSessionFactory().getCurrentSession()); ead.getSession().beginTransaction(); ead.makePersistent(ea); ead.makePersistent(otherEA); ead.getSession().getTransaction().commit(); } On commiting the current transaction, I can see in the logs that a ConstraintViolationException is thrown: 16:08:47,571 DEBUG SQL:111 - insert into ExpertiseArea (VERSION, name, id) values (?, ?, ?) Hibernate: insert into ExpertiseArea (VERSION, name, id) values (?, ?, ?) 16:08:47,571 DEBUG SQL:111 - insert into ExpertiseArea (VERSION, name, id) values (?, ?, ?) Hibernate: insert into ExpertiseArea (VERSION, name, id) values (?, ?, ?) 16:08:47,572 WARN JDBCExceptionReporter:100 - SQL Error: -104, SQLState: 23505 16:08:47,572 ERROR JDBCExceptionReporter:101 - integrity constraint violation: unique constraint or index violation; SYS_CT_10036 table: EXPERTISEAREA 16:08:47,573 ERROR AbstractFlushingEventListener:324 - Could not synchronize database state with session org.hibernate.exception.ConstraintViolationException: Could not execute JDBC batch update So I would expect the test to pass, since the expected ConstraintViolationException is thrown. However, the test never completes (neither pass nor fails) and I have to manually kill the test runner. What's the correct way to test this?

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• cast value of a textbox to a textbox in another form

  - by simon

  I'm trying to paste the values from a textbox in form1 to textbox in form2. I did that, but while i upgraded my aplication it stopped to work. I allso need that couse i get an error(incorect data type in conditional statement) when i want to insert a value from a textbox (to a access database) that's not on the form that makes the insert statemen. the code: string textFromForm1; public Form2() { InitializeComponent(); } public void textBox1_TextChanged(object sender, EventArgs e) { } private void button1_Click(object sender, EventArgs e) { using (Form3 obrok = new Form3()) obrok.ShowDialog(); } private void button3_Click(object sender, EventArgs e) { this.Hide(); } private void button2_Click(object sender, EventArgs e) { } private void textBox1_TextChanged_1(object sender, EventArgs e) { } Form1 bmr=new Form1(); int masa; private void Form2_Load(object sender, EventArgs e) { textBox1.Text = bmr.masaTextBox.Text; } the code for insert statement: string conString = "Provider=Microsoft.Jet.OLEDB.4.0;" + "Data Source=C:\Users\Simon\Desktop\save.mdb"; OleDbConnection empConnection = new OleDbConnection(conString); string insertStatement = "INSERT INTO obroki_save " + "([ID_uporabnika],[ID_zivila],[skupaj_kalorij]) " + "VALUES (@ID_uporabnika,@ID_zivila,@skupaj_kalorij)"; OleDbCommand insertCommand = new OleDbCommand(insertStatement, empConnection); insertCommand.Parameters.Add("@ID_uporabnika", OleDbType.Char).Value = users.iDTextBox.Text; insertCommand.Parameters.Add("@ID_zivila", OleDbType.Char).Value = iDTextBox.Text; insertCommand.Parameters.Add("@skupaj_kalorij", OleDbType.Char).Value = textBox1.Text; empConnection.Open(); try { int count = insertCommand.ExecuteNonQuery(); } catch (OleDbException ex) { MessageBox.Show(ex.Message); } finally { empConnection.Close(); textBox1.Clear(); textBox2.Clear(); textBox3.Clear(); textBox4.Clear(); textBox5.Clear(); }

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• Sharepoint OLE DB - field not updateable

  - by Pandincus

  I need to write a simple C# .NET application to retrieve, update, and insert some data in a Sharepoint list. I am NOT a Sharepoint developer, and I don't have control over our Sharepoint server. I would prefer not to have to develop this in a proper sharepoint development environment simply because I don't want to have to deploy my application on the Sharepoint server -- I'd rather just access data externally. Anyway, I found out that you can access Sharepoint data using OLE DB, and I tried it successfully using some ADO.NET: var db = DatabaseFactory.CreateDatabase(); DataSet ds = new DataSet(); using (var command = db.GetSqlStringCommand("SELECT * FROM List")) { db.LoadDataSet(command, ds, "List"); } The above works. However, when I try to insert: using (var command = db.GetSqlStringCommand("INSERT INTO List ([HeaderName], [Description], [Number]) VALUES ('Blah', 'Blah', 100)")) { db.ExecuteNonQuery(command); } I get this error: Cannot update 'HeaderName'; field not updateable. I did some Googling and apparently you cannot insert data through OLE DB! Does anyone know if there are some possible workarounds? I could try using Sharepoint Web Services, but I tried that initially and was having a heck of a time authenticating. Is that my only option?

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• concatenate rows of Clob with plsql

  - by david K

  Hi, late considere i conider if got a table who got an Id and a clob content like: create table v_EXAMPLE_L ( nip number, xmlcontent clob ); we insert our data: Insert into V_EXAMPLE_L (NIP,XMLCONTENT) values (17852,'delta548484646846484'); Insert into V_EXAMPLE_L (NIP,XMLCONTENT) values (17852,'omega545648468484'); Insert into V_EXAMPLE_L (NIP,XMLCONTENT) values (17852, 'gamma54564846qsdqsdqsdqsd8484'); i'm trying do do a function that concatenate the rows of the clob that gone be the result of a select , i mean without having to give multiple parameter about the name of table or such , i should only give here the column that contain the clobs , and she should handle the rest!. CREATE OR REPLACE function assemble_clob(q varchar2) return clob is v_clob clob; tmp_lob clob; hold VARCHAR2(4000); --cursor c2 is select xmlcontent from V_EXAMPLE_L where id=17852 cur sys_refcursor; begin OPEN cur FOR q; LOOP FETCH cur INTO tmp_lob; EXIT WHEN cur%NOTFOUND; --v_clob := v_clob || XMLTYPE.getClobVal(tmp_lob.xmlcontent); v_clob := v_clob || tmp_lob; END LOOP; return (v_clob); --return (dbms_xmlquery.getXml( dbms_xmlquery.set_context("Select 1 from dual")) ) end assemble_clob; the function is broken ... (if anybody could give me a help, thanks a lot, and i'm noob in sql so ....). and thanks

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• asp.net Impersonate User for network resource access

  - by lonelycoder

  code: System.Security.Principal.WindowsImpersonationContext impersonationContext; impersonationContext = ((System.Security.Principal.WindowsIdentity)User.Identity).Impersonate(); //access network resources. impersonationContext.Undo(); web.config: <authentication mode="Windows"> </authentication> <identity impersonate="true" userName="user" password="password"></identity> As clear from web.config file, the app runs in an impersonated mode. I need to impersonate temporarily on top of that to access a network resource. I do that as shown above. This works fine on server if I browse to the website on the local IE installed on the server but when I access the app from my PC or any other PC, I get a access denied. Btw, this is all within an enterprise domain environment. so IE in both cases is passing a valid authenticated token. Any ideas what is going on. thanks.

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• WCF Service Impersonation

  - by robalot

  Good Day Everyone... Apparently, I'm not setting-up impersonation correctly for my WCF service. I do NOT want to set security on a method-by-method basis (in the actual code-behind). The service (at the moment) is open to be called by everyone on the intranet. So my questions are… Q: What web-config tags am I missing? Q: What do I need to change in the web-config to make impersonation work? The Service Web.config Looks Like... <configuration> <system.web> <authorization> <allow users="?"/> </authorization> <authentication mode="Windows"/> <identity impersonate="true" userName="MyDomain\MyUser" password="MyPassword"/> </system.web> <system.serviceModel> <services> <service behaviorConfiguration="wcfFISH.DataServiceBehavior" name="wcfFISH.DataService"> <endpoint address="" binding="wsHttpBinding" contract="wcfFISH.IFishData"> <identity> <dns value="localhost"/> </identity> </endpoint> <endpoint address="mex" binding="mexHttpBinding" contract="IMetadataExchange" /> </service> </services> <behaviors> <serviceBehaviors> <behavior name="wcfFISH.DataServiceBehavior"> <serviceMetadata httpGetEnabled="false"/> <serviceDebug includeExceptionDetailInFaults="false"/> </behavior> </serviceBehaviors> </behaviors> </system.serviceModel> </configuration>

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• Suggest a good method with least lookup time complexity

  - by Amrish

  I have a structure which has 3 identifier fields and one value field. I have a list of these objects. To give an analogy, the identifier fields are like the primary keys to the object. These 3 fields uniquely identify an object. Class { int a1; int a2; int a3; int value; }; I would be having a list of say 1000 object of this datatype. I need to check for specific values of these identity key values by passing values of a1, a2 and a3 to a lookup function which would check if any object with those specific values of a1, a2 and a3 is present and returns that value. What is the most effective way to implement this to achieve a best lookup time? One solution I could think of is to have a 3 dimensional matrix of length say 1000 and populate the value in it. This has a lookup time of O(1). But the disadvantages are. 1. I need to know the length of array. 2. For higher identity fields (say 20), then I will need a 20 dimension matrix which would be an overkill on the memory. For my actual implementation, I have 23 identity fields. Can you suggest a good way to store this data which would give me the best look up time?

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