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• MS Query Analizer/Management Studio replacement?

  - by kprobst

  I've been using SQL Server since version 6.5 and I've always been a bit amazed at the fact that the tools seem to be targeted to DBAs rather than developers. I liked the simplicity and speed of the Query Analizer for example, but hated the built-in editor, which was really no better than a syntax coloring-capable Notepad. Now that we have Management Studio the management part seems a bit better but from a developer standpoint the tools is even worse. Visual Studio's excellent text editor... without a way to customize keyboard bindings!? Don't get me started on how unusable is the tree-based management hierarchy. Why can't I re-root the tree on a list of stored procs for example the way the Enterprise Manager used to allow? Now I have a treeview that needs to be scrolled horizontally, which makes it eminently useless. The SQL server support in Visual Studio is fantastic for working with stored procedures and functions, but it's terrible as a general ad hoc data query tool. I've tried various tools over the years but invariably they seem to focus on the management side and shortchange the developer in me. I just want something with basic admin capabilities, good keyboard support and requisite DDL functionality (ideally something like the Query Analyzer). At this point I'm seriously thinking of using vim+sqlcmd and a console... I'm that desperate :) Those of you who work day in and day out with SQL Server and Visual Studio... do you find the tools to be adequate? Have you ever wished they were better and if you have found something better, could you share please? Thanks!

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• C#'s equivalent to VB.Net's DirectCast?

  - by Collin Sauve

  This has probably been asked before, but if it has, I can't find it. Does C# have an equivalent to VB.Net's DirectCast? I am aware that it has () casts and the 'as' keyword, but those line up to CType and TryCast. To be clear, these keywords do the following; CType/() casts: If it is already the correct type, cast it, otherwise look for a type converter and invoke it. If no type converter is found, throw an InvalidCastException. TryCast/"as" keyword: If it is the correct type, cast it, otherwise return null. DirectCast: If it is the correct type, cast it, otherwise throw an InvalidCastException. EDIT: After I have spelled out the above, some people have still responded that () is equivalent, so I will expand further upon why this is not true. DirectCast only allows for either Narrowing or Widening conversions on inheritance tree, it does not support conversions across different branches like () does. ie: C#, this compiles and runs: //This code uses a type converter to go across an inheritance tree double d = 10; int i = (int)d; VB.Net, this does NOT COMPILE 'Direct cast can only go up or down a branch, never across to a different one. Dim d as Double= 10 Dim i as Integer = DirectCast(d, Integer) The equivalent in VB.Net to my C# code is CType: 'This compiles and runs Dim d as Double= 10 Dim i as Integer = CType(d, Integer) (Edit again, I was originally using strings, I changed it to double... sorry)

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• Hierarchical object model with property inheritance and event bubbling?

  - by Winston Fassett

  I'm writing a document-based client application and I need a DOM or WPF-like, but non-visual model that: Is a tree composed of elements Can accept an unlimited number of custom properties that get/set any CLR type, including collections. Can inherit their values from their parent Can inherit their default values from an ancestor Can be derived/calculated from other properties, ancestors, or descendants Support event bubbling / tunneling There will be a core set of properties but other plugins may add their own or even create custom documents Supports full inspection by the owning document in order to persist the tree and attributes in an XML format. I realize that's a tall order but I was really hoping there would be something out there to help me get started. Unfortunately WPF DependencyObjects are too closed, proprietary, and coupled to WPF to be of any use as a document model. My needs also have a strong resemblance to the HTML DOM but I haven't been able to find any clean DOM implementations that could be decoupled from HTML or ported to .NET. My current platform is .NET/C# but if anyone knows of anything that might be useful for inspiration or embedding, regardless of the platform, I'd love to know.

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• binding nested json object value to a form field

  - by Jack

  I am building a dynamic form to edit data in a json object. First, if something like this exists let me know. I would rather not build it but I have searched many times for a tool and have found only tree like structures that require entering quotes. I would be happy to treat all values as strings. This edit functionality is for end users so it needs to be easy an not intimidating. So far I have code that generates nested tables to represent a json object. For each value I display a form field. I would like to bind the form field to the associated nested json value. If I could store a reference to the json value I would build an array of references to each value in a json object tree. I have not found a way to do that with javascript. My last resort approach will be to traverse the table after edits are made. I would rather have dynamic updates but a single submit would be better than nothing. Any ideas? // the json in files nests only a few levels. Here is the format of a simple case, { "researcherid_id":{ "id_key":"researcherid_id", "description":"Use to retrieve bibliometric data", "url_template" :[ { "name": "Author Detail", "url": "http://www.researcherid.com/rid/${key}" } ] } } $.get('file.json',make_json_form); function make_json_form(response) { dataset = $.secureEvalJSON(response); // iterate through the object and generate form field for string values. } // Then after the form is edited I want to display the raw updated json (then I want to save it but that is for another thread) // now I iterate through the form and construct the json object // I would rather have the dataset object var updated on focus out after each edit. function show_json(form_id){ var r = {}; var el = document.getElementById(form_id); table_to_json(r,el,null); $('body').html(formattedJSON(r)); }

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• Hierarchical/Nested Database Structure for Comments

  - by Stephen Melrose

  Hi, I'm trying to figure out the best approach for a database schema for comments. The problem I'm having is that the comments system will need to allow nested/hierarchical comments, and I'm not sure how to design this out properly. My requirements are, Comments can be made on comments, so I need to store the tree hierarchy I need to be able to query the comments in the tree hierarchy order, but efficiently, preferably in a fast single query, but I don't know if this is possible I'd need to make some wierd queries, e.g. pull out the latest 5 root comments, and a maximum of 3 children for each one of those I read an article on the MySQL website on this very subject, http://dev.mysql.com/tech-resources/articles/hierarchical-data.html The "Nested Set Model" in theory sounds like it will do what I need, except I'm worried about querying the thing, and also inserting. If this is the right approach, How would I do my 3rd requirement above? If I have 2000 comments, and I add a new sub-comment on the first comment, that will be a LOT of updating to do. This doesn't seem right to me? Or is there a better approach for the type of data I'm wanting to store and query? Thank you

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• When to choose which machine learning classifier?

  - by LM

  Suppose I'm working on some classification problem. (Fraud detection and comment spam are two problems I'm working on right now, but I'm curious about any classification task in general.) How do I know which classifier I should use? (Decision tree, SVM, Bayesian, logistic regression, etc.) In which cases is one of them the "natural" first choice, and what are the principles for choosing that one? Examples of the type of answers I'm looking for (from Manning et al.'s "Introduction to Information Retrieval book": http://nlp.stanford.edu/IR-book/html/htmledition/choosing-what-kind-of-classifier-to-use-1.html): a. If your data is labeled, but you only have a limited amount, you should use a classifier with high bias (for example, Naive Bayes). [I'm guessing this is because a higher-bias classifier will have lower variance, which is good because of the small amount of data.] b. If you have a ton of data, then the classifier doesn't really matter so much, so you should probably just choose a classifier with good scalability. What are other guidelines? Even answers like "if you'll have to explain your model to some upper management person, then maybe you should use a decision tree, since the decision rules are fairly transparent" are good. I care less about implementation/library issues, though. Also, for a somewhat separate question, besides standard Bayesian classifiers, are there 'standard state-of-the-art' methods for comment spam detection (as opposed to email spam)? [Not sure if stackoverflow is the best place to ask this question, since it's more machine learning than actual programming -- if not, any suggestions for where else?]

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• Duplicate elements when adding XElement to XDocument

  - by Andy

  I'm writing a program in C# that will go through a bunch of config.xml files and update certain elements, or add them if they don't exist. I have the portion down that updates an element if it exists with this code: XDocument xdoc = XDocument.Parse(ReadFile(_file)); XElement element = xdoc.Elements("project").Elements("logRotator") .Elements("daysToKeep").Single(); element.Value = _DoRevert; But I'm running into issues when I want to add an element that doesn't exist. Most of the time part of the tree is in place and when I use my code it adds another identical tree, and that causes the program reading the xml to blow up. here is how I am attempting to do it xdoc.Element("project").Add(new XElement("logRotator", new XElement("daysToKeep", _day))); and that results in a structure like this(The numToKeep tag was already there): <project> <logRotator> <daysToKeep>10</daysToKeep> </logRotator> <logRotator> <numToKeep>13</numToKeep> </logRotator> </project> but this is what I want <project> <logRotator> <daysToKeep>10</daysToKeep> <numToKeep>13</numToKeep> </logRotator> </project>

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• find the children in jquery

  - by armin etemadi

  i have a tree structure,there is an unordered list(ul) in that tree.i have li items in it,and in that li items it could be a span or an ul list. this is one part of my codes : <li id="main_li"> <div class="first_division"></div> <span>products</span> <ul style="display: block;"> <li> <div class="division1"></div> <span>products_cat_1</span> <ul style="display: none;"> <li> <span>products_cat_1_milk</span> </li> </ul> </li> <li> <span>products_yoghurt</span> </li> <li> <span>products_butter</span> </li> </ul> </li> i want to access li elements in ul tag where the parent li id is "main_li",i want to get it done by clicking on the span within li. how can i do this with jquery?

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• What is the best approach to 2D collision detection on the iPhone?

  - by Magic Bullet Dave

  Been working on this problem of collision detection and there appears to be 3 main approaches I could take: Sprite and mask approach. (AND the overlap of the sprites and check for a non-zero number in the resulting sprite pixel data). Bounding circles, rectangles or polygons. (Create one or more shapes that enclose the sprites and do the basic maths to check for overlaps). Use an existing sprite library. The first approach, even though it would have been the way I would have done it in the old days of 16x16 sprite blocks, it appears that there just isn’t an easy way of getting at the individual image pixel data and/or alpha channel within Quartz (or OPENGL for that matter). Detecting the overlap of the bounding box is easy, but then creating a 3rd image from the overlap and then testing it for pixels is complicated and my gut feel is that even if we could get it to work would be slow. Am I missing something neat here? The second approach involves dividing up our sprites into several polygons and testing them for overlaps. The more polygons the more accurate the collision detection. The benefit is that it is fast, and can be accurate. The downside is it makes the sprite creation more complicated. i.e., we have to create the polygons for each sprite. For speed the best approach is to create a tree of polygons. The 3rd approach I’m not sure about as it involves buying code (or using an open source licence). I am not sure what the best library to use is or whether this would make life easier or give us a problem integrating this into our app. So in short I am favouring the polygon and tree approach and would appreciate you views on this before I go and write lots of code. Best regards Dave

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• Rtti data manipulation and consistency in Delphi 2010

  - by Coco

  Has anyone an idea, how I can make TValue using a reference to the original data? In my serialization project, I use (as suggested in XML-Serialization) a generic serializer which stores TValues in an internal tree-structure (similar to the MemberMap in the example). This member-tree should also be used to create a dynamic setup form and manipulate the data. My idea was to define a property for the Data: TDataModel <T> = class {...} private FData : TValue; function GetData : T; procedure SetData (Value : T); public property Data : T read GetData write SetData; end; The implementation of the GetData, SetData Methods: procedure TDataModel <T>.SetData (Value : T); begin FData := TValue.From <T> (Value); end; procedure TDataModel <T>.GetData : T; begin Result := FData.AsType <T>; end; Unfortunately, the TValue.From method always makes a copy of the original data. So whenever the application makes changes to the data, the DataModel is not updated and vice versa if I change my DataModel in a dynamic form, the original data is not affected. Sure I could always use the Data property before and after changing anything, but as I use lot of Rtti inside my DataModel, I do not realy want to do this anytime. Perhaps someone has a better suggestion?

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• Why does a sub-class class of a class have to be static in order to initialize the sub-class in the

  - by Alex

  So, the question is more or less as I wrote. I understand that it's probably not clear at all so I'll give an example. I have class Tree and in it there is the class Node, and the empty constructor of Tree is written: public class RBTree { private RBNode head; public RBTree(RBNode head,RBTree leftT,RBTree rightT){ this.head=head; this.head.leftT.head.father = head; this.head.rightT.head.father = head; } public RBTree(RBNode head){ this(head,new RBTree(),new RBTree()); } public RBTree(){ this(new RBNode(),null,null); } public class RBNode{ private int value; private boolean isBlack; private RBNode father; private RBTree leftT; private RBTree rightT; } } Eclipse gives me the error: "No enclosing instance of type RBTree is available due to some intermediate constructor invocation" for the "new RBTree()" in the empty constructor. However, if I change the RBNode to be a static class, there is no problem. So why is it working when the class is static. BTW, I found an easy solution for the cunstructor: public RBTree(){ this.head = new RBNode(); } So, I have no idea what is the problem in the first piece of code.

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• C++ destructos causing crash's

  - by larsonator

  ok, so i got a some what intricate program that simulates the uni systems of students, units, and students enrolling in units. Students are stored in a binary search tree, Units are stored in a standard list. Student has a list of Unit Pointers, to store which units he/she is enrolled in Unit has a list of Student pointers, to store students which are enrolled in that unit. The unit collections (storing units in a list) as made as a static variable where the main function is, as is the Binary search tree of students. when its finaly time to close the program, i call the destructors of each. but at some stage, during the destructors on the unit side, Unhandled exception at 0x002e4200 in ClassAllocation.exe: 0xC0000005: Access violation reading location 0x00000000. UnitCollection destructor: UnitCol::~UnitCol() { list<Unit>::iterator itr; for(itr = UnitCollection.begin(); itr != UnitCollection.end();) { UnitCollection.pop_front(); itr = UnitCollection.begin(); } } Unit Destructor Unit::~Unit() { } now i got the same sorta problem on the student side of things BST destructors void StudentCol::Destructor(const BTreeNode * r) { if(r!= 0) { Destructor(r->getLChild()); Destructor(r->getRChild()); delete r; } } StudentCol::~StudentCol() { Destructor(root); } Student Destructor Student::~Student() { } so yeah any help would be greatly appreciated

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• Dynamic Hierarchical Javascript Object Loop

  - by user1684586

  var treeData = {"name" : "A", "children" : [ {"name" : "B", "children": [ {"name" : "C", "children" :[]} ]} ]}; THE ARRAY BEFORE SHOULD BE EMPTY. THE ARRAY AFTER SHOULD BE POPULATED DEPENDING ON THE NUMBER OF NODES NEEDED THAT WILL BE DEFINED FROM A DYNAMIC VALUE THAT IS PASSED. I would like to build the hierarchy dynamically with each node created as a layer/level in the hierarchy having its own array of nodes. THIS SHOULD FORM A TREE STRUCTURE. This is hierarchy structure is described in the above code. This code has tree level simple for demonstrating the layout of the hierarchy of values. There should be a root node, and an undefined number of nodes and levels to make up the hierarchy size. Nothing should be fixed besides the root node. I do not need to read the hierarchy, I need to construct it. The array should start {"name" : "A", "children" : []} and every new node as levels would be created {"name" : "A", "children" : [HERE-{"name" : "A", "children" : []}]}. In the child array, going deeper and deeper. Basically the array should have no values before the call, except maybe the root node. After the function call, the array should comprise of the required nodes of a number that may vary with every call. Every child array will contain one or more node values. There should be a minimum of 2 node levels, including the root. It should initially be a Blank canvas, that is no predefined array values.

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• C++ destructors causing crash's

  - by larsonator

  ok, so i got a some what intricate program that simulates the uni systems of students, units, and students enrolling in units. Students are stored in a binary search tree, Units are stored in a standard list. Student has a list of Unit Pointers, to store which units he/she is enrolled in Unit has a list of Student pointers, to store students which are enrolled in that unit. The unit collections (storing units in a list) as made as a static variable where the main function is, as is the Binary search tree of students. when its finaly time to close the program, i call the destructors of each. but at some stage, during the destructors on the unit side, Unhandled exception at 0x002e4200 in ClassAllocation.exe: 0xC0000005: Access violation reading location 0x00000000. UnitCollection destructor: UnitCol::~UnitCol() { list<Unit>::iterator itr; for(itr = UnitCollection.begin(); itr != UnitCollection.end();) { UnitCollection.pop_front(); itr = UnitCollection.begin(); } } Unit Destructor Unit::~Unit() { } now i got the same sorta problem on the student side of things BST destructors void StudentCol::Destructor(const BTreeNode * r) { if(r!= 0) { Destructor(r->getLChild()); Destructor(r->getRChild()); delete r; } } StudentCol::~StudentCol() { Destructor(root); } Student Destructor Student::~Student() { } so yeah any help would be greatly appreciated

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• TicTacToe strategic reduction

  - by NickLarsen

  I decided to write a small program that solves TicTacToe in order to try out the effect of some pruning techniques on a trivial game. The full game tree using minimax to solve it only ends up with 549,946 possible games. With alpha-beta pruning, the number of states required to evaluate was reduced to 18,297. Then I applied a transposition table that brings the number down to 2,592. Now I want to see how low that number can go. The next enhancement I want to apply is a strategic reduction. The basic idea is to combine states that have equivalent strategic value. For instance, on the first move, if X plays first, there is nothing strategically different (assuming your opponent plays optimally) about choosing one corner instead of another. In the same situation, the same is true of the center of the walls of the board, and the center is also significant. By reducing to significant states only, you end up with only 3 states for evaluation on the first move instead of 9. This technique should be very useful since it prunes states near the top of the game tree. This idea came from the GameShrink method created by a group at CMU, only I am trying to avoid writing the general form, and just doing what is needed to apply the technique to TicTacToe. In order to achieve this, I modified my hash function (for the transposition table) to enumerate all strategically equivalent positions (using rotation and flipping functions), and to only return the lowest of the values for each board. Unfortunately now my program thinks X can force a win in 5 moves from an empty board when going first. After a long debugging session, it became apparent to me the program was always returning the move for the lowest strategically significant move (I store the last move in the transposition table as part of my state). Is there a better way I can go about adding this feature, or a simple method for determining the correct move applicable to the current situation with what I have already done?

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• macro collapse all in solution visual studio 2010

  - by rod

  Hi All, I found the CollapseAll macro online that has worked for me in vs2005 and vs2008. However, this half way works in vs2010. It looks like it only collapses the top nodes and not any subnodes that may be expanded? any ideas? Thanks, rod. Sub CollapseAll() ' Get the the Solution Explorer tree Dim UIHSolutionExplorer As UIHierarchy UIHSolutionExplorer = DTE.Windows.Item(Constants.vsext_wk_SProjectWindow).Object() ' Check if there is any open solution If (UIHSolutionExplorer.UIHierarchyItems.Count = 0) Then ' MsgBox("Nothing to collapse. You must have an open solution.") Return End If ' Get the top node (the name of the solution) Dim UIHSolutionRootNode As UIHierarchyItem UIHSolutionRootNode = UIHSolutionExplorer.UIHierarchyItems.Item(1) UIHSolutionRootNode.DTE.SuppressUI = True ' Collapse each project node Dim UIHItem As UIHierarchyItem For Each UIHItem In UIHSolutionRootNode.UIHierarchyItems 'UIHItem.UIHierarchyItems.Expanded = False If UIHItem.UIHierarchyItems.Expanded Then Collapse(UIHItem) End If Next ' Select the solution node, or else when you click ' on the solution window ' scrollbar, it will synchronize the open document ' with the tree and pop ' out the corresponding node which is probably not what you want. UIHSolutionRootNode.Select(vsUISelectionType.vsUISelectionTypeSelect) UIHSolutionRootNode.DTE.SuppressUI = False End Sub Private Sub Collapse(ByVal item As UIHierarchyItem) For Each eitem As UIHierarchyItem In item.UIHierarchyItems If eitem.UIHierarchyItems.Expanded AndAlso eitem.UIHierarchyItems.Count > 0 Then Collapse(eitem) End If Next item.UIHierarchyItems.Expanded = False End Sub End Module

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• I did my own web framework: now, how keep it sync with applications? must I use versions?

  - by Daniel Koch

  ... and I did the first web application using it, now I'm going to create the second. In this first web application I enhanced the framework's core library with new things and promptly updated framework branch. I'm using bazaar to keep framework and web application committed. The application was in the beginning, a full branch of framework source tree, now I'm updating framework manually at every change on core files. (copying changed files from web app to framework's branch). With this second web application that I'm going to create, I need to know about versions (or revisions) which the application is based. If I found a bug in this version I can fix and then sync files with first web application no worrying: functions will be the same to this application. If I'm going to make changes in core (new behavior, new functions in library or something new in source tree) it must be named as "new version". What's the best way to do this? Because I'm using a Distributed Version Control System (bazaar), I'm not dealing with VERSIONS, but revision numbers that change every time. Please fresh my mind with new ideas.

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• How to calculate commision based on referred memebrs?

  - by RAJKISHOR SAHU

  Hello everybody, I am developing a small software in C# WPF for a consultancy which does chain system business. I have coded tree structure to show who referred whom. Now it has commission depending on level. If 1 referred 2 & 3 then 1 will get level-1 commission. If 2 referred 4, 5 & 3 referred 6, 7 then 1 will receive level-2 commission. This chain will go on to certain total number. My problem is how I would implement this logic; I am able to calculate who has referred how many members via UDF written for adding TreeViewItem to TreeView. Or tell me how I can count items in treeview in certain level? Node adding UDF: public void AddNodes(int uid, TreeViewItem tSubNode) { string query = "select fullname, id from members where refCode=" + uid + ";"; MySqlCommand cmd = new MySqlCommand(query, db.conn); MySqlDataAdapter _DA = new MySqlDataAdapter(cmd); DataTable _DT = new DataTable(); tSubNode.IsExpanded = true; _DA.Fill(_DT); foreach (DataRow _dr in _DT.Rows) { TreeViewItem tNode = new TreeViewItem(); tNode.Header = _dr["fullname"].ToString()+" ("+_dr["id"].ToString()+")"; tSubNode.Items.Add(tNode); if (db.HasMembers(Convert.ToInt32(_dr["id"].ToString()))) { AddNodes(Convert.ToInt32(_dr["id"]), tNode); } } //This line tracks who has referred how many members Console.WriteLine("Tree node Count : "+tSubNode.Items.Count.ToString()+", UID "+uid); } Help me PLEASE!!!!

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• NoSQL for filesystem storage organization and replication?

  - by wheaties

  We've been discussing design of a data warehouse strategy within our group for meeting testing, reproducibility, and data syncing requirements. One of the suggested ideas is to adapt a NoSQL approach using an existing tool rather than try to re-implement a whole lot of the same on a file system. I don't know if a NoSQL approach is even the best approach to what we're trying to accomplish but perhaps if I describe what we need/want you all can help. Most of our files are large, 50+ Gig in size, held in a proprietary, third-party format. We need to be able to access each file by a name/date/source/time/artifact combination. Essentially a key-value pair style look-up. When we query for a file, we don't want to have to load all of it into memory. They're really too large and would swamp our server. We want to be able to somehow get a reference to the file and then use a proprietary, third-party API to ingest portions of it. We want to easily add, remove, and export files from storage. We'd like to set up automatic file replication between two servers (we can write a script for this.) That is, sync the contents of one server with another. We don't need a distributed system where it only appears as if we have one server. We'd like complete replication. We also have other smaller files that have a tree type relationship with the Big files. One file's content will point to the next and so on, and so on. It's not a "spoked wheel," it's a full blown tree. We'd prefer a Python, C or C++ API to work with a system like this but most of us are experienced with a variety of languages. We don't mind as long as it works, gets the job done, and saves us time. What you think? Is there something out there like this?

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• Why does the JSF action tag handler in JSP invoke rendering immediately after creation?

  - by Pentius

  Dear fellows, I read the article "Improving JSF by Dumping JSP" from Hans Bergsten. There I read the following: The JSP container processes the page and invokes the JSF action tag handlers as they are encountered. A JSF tag handler looks for the JSF component it represents in the component tree. If it can't find the component, it creates it and adds it to the component tree. It then asks the component to render itself. and furthermore On the first request, the action creates its component and asks it to render itself. I understand that the immediate rendering after the creation of the component is the problem here (The reference to the input component can't be resolved in the example). That's one point, why JSF doesn't fit with JSP. But it reads as if the action tag handler itself would ask the component to render. Or is it JSP that triggers the rendering directly after the action tag handler created the component. If it is the action tag handler, I don't understand, why this is the fault of JSP. What is different here than from JSF intended? Thanks for your help, I need this for my thesis.

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• Searching in graphs trees with Depth/Breadth first/A* algorithms

  - by devoured elysium

  I have a couple of questions about searching in graphs/trees: Let's assume I have an empty chess board and I want to move a pawn around from point A to B. A. When using depth first search or breadth first search must we use open and closed lists ? This is, a list that has all the elements to check, and other with all other elements that were already checked? Is it even possible to do it without having those lists? What about A*, does it need it? B. When using lists, after having found a solution, how can you get the sequence of states from A to B? I assume when you have items in the open and closed list, instead of just having the (x, y) states, you have an "extended state" formed with (x, y, parent_of_this_node) ? C. State A has 4 possible moves (right, left, up, down). If I do as first move left, should I let it in the next state come back to the original state? This, is, do the "right" move? If not, must I transverse the search tree every time to check which states I've been to? D. When I see a state in the tree where I've already been, should I just ignore it, as I know it's a dead end? I guess to do this I'd have to always keep the list of visited states, right? E. Is there any difference between search trees and graphs? Are they just different ways to look at the same thing?

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• PEAR:DB connection parameters

  - by Markus Ossi

  I just finished my first PHP site and now I have a security-related question. I used PEAR:DB for the database connection and made a separate parameter file for it. How should I hide this parameter file? I found a guide (http://www.kitebird.com/articles/peardb.html) that says: Another way to specify connection parameters is to put them in a separate file that you reference from your main script. ... It also enables you to move the parameter file outside of the web server's document tree, which prevents its contents from being displayed literally if the server becomes misconfigured and starts serving PHP scripts as plain text. I have now put my file in a directory like this /include/db_parameters.inc However, if I go to this URL, the web server shows me the contents of the file including my database username and password. From what I've understood, I should protect this file so, that even though PHP would be served as text, nobody could read this. What does outside of web server's document tree mean here? Put the PHP file out of public_html directory altogether deeper into the server file system? Some CHMOD?

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• Creating a Linq->HQL provider

  - by Mike Q

  Hi all, I have a client application that connects to a server. The server uses hibernate for persistence and querying so it has a set of annotated hibernate objects for persistence. The client sends HQL queries to the server and gets responses back. The client has an auto-generated set of objects that match the server hibernate objects for query results and basic persistence. I would like to support using Linq to query as well as Hql as it makes the queries typesafe and quicker to build (no more typos in HQL string queries). I've looked around at the following but I can't see how to get them to fit with what I have. NHibernate's Linq provider - requires using NHibernate ISession and ISessionFactory, which I don't have LinqExtender - requires a lot of annotations on the objects and extending a base type, too invasive What I really want is something that will generate give me a nice easy to process structure to build the HQL queries from. I've read most of a 15 page article written by one of the C# developers on how to create custom providers and it's pretty fraught, mainly because of the complexity of the expression tree. Can anyone suggest an approach for implementing Linq - HQL translation? Perhaps a library that will the cleanup of the expression tree into something more SQL/HQLish. I would like to support select/from/where/group by/order by/joins. Not too worried about subqueries.

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• Searching Natural Language Sentence Structure

  - by Cerin

  What's the best way to store and search a database of natural language sentence structure trees? Using OpenNLP's English Treebank Parser, I can get fairly reliable sentence structure parsings for arbitrary sentences. What I'd like to do is create a tool that can extract all the doc strings from my source code, generate these trees for all sentences in the doc strings, store these trees and their associated function name in a database, and then allow a user to search the database using natural language queries. So, given the sentence "This uploads files to a remote machine." for the function upload_files(), I'd have the tree: (TOP (S (NP (DT This)) (VP (VBZ uploads) (NP (NNS files)) (PP (TO to) (NP (DT a) (JJ remote) (NN machine)))) (. .))) If someone entered the query "How can I upload files?", equating to the tree: (TOP (SBARQ (WHADVP (WRB How)) (SQ (MD can) (NP (PRP I)) (VP (VB upload) (NP (NNS files)))) (. ?))) how would I store and query these trees in a SQL database? I've written a simple proof-of-concept script that can perform this search using a mix of regular expressions and network graph parsing, but I'm not sure how I'd implement this in a scalable way. And yes, I realize my example would be trivial to retrieve using a simple keyword search. The idea I'm trying to test is how I might take advantage of grammatical structure, so I can weed-out entries with similar keywords, but a different sentence structure. For example, with the above query, I wouldn't want to retrieve the entry associated with the sentence "Checks a remote machine to find a user that uploads files." which has similar keywords, but is obviously describing a completely different behavior.

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• When is the reintegrate option really necessary?

  - by Tor Hovland

  If you always sync a feature branch before you merge it back, why do you really have to use the --reintegrate option? The Subversion book says: When merging your branch back to the trunk, however, the underlying mathematics is quite different. Your feature branch is now a mishmosh of both duplicated trunk changes and private branch changes, so there's no simple contiguous range of revisions to copy over. By specifying the --reintegrate option, you're asking Subversion to carefully replicate only those changes unique to your branch. (And in fact, it does this by comparing the latest trunk tree with the latest branch tree: the resulting difference is exactly your branch changes!) So the --reintegrate option only merges the changes that are unique to the feature branch. But if you always sync before merge (which is a recommended practice, in order to deal with any conflicts on the feature branch), then the only changes between the branches are the changes that are unique to the feature branch, right? And if Subversion tries to merge code that is already on the target branch, it will just do nothing, right? In this blog post, Mark Phippard writes: http://blogs.open.collab.net/svn/2008/07/subversion-merg.html If we include those synched revisions, then we merge back changes that already exist in trunk. This yields unnecessary and confusing conflicts. Can somebody give me an example of when dropping reintegrate gives me unnecessary conflicts?

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