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  • My Zend Framework 'quoting' mess.

    - by tharkun
    I've got a probably very simple issue to which I can't find a satisfactory (subjectively seen) answer in the Zend Framework manual or elsewhere... There are so many ways how I can hand over my php variables to my sql queries that I lost the overview and probably I lack some understanding about quoting in general. Prepared Statements $sql = "SELECT this, that FROM table WHERE id = ? AND restriction = ?"; $stmt = $this->_db->query($sql, array($myId, $myValue)); $result = $stmt->fetchAll(); I understand that with this solution I don't need to quote anything because the db handles this for me. Querying Zend_Db_Table and _Row objects over the API $users = new Users(); a) $users->fetchRow('userID = ' . $userID); b) $users->fetchRow('userID = ' . $users->getAdapter()->quote($userID, 'INTEGER')); c) $users->fetchRow('userID = ?', $userID); d) $users->fetchRow('userID = ?', $users->getAdapter()->quote($userID, 'INTEGER')); Questions I understand that a) is not ok because it's not quoted at all. But what about the other versions, what's the best? Is c) being treated like a statement and automatically quoted or do I need to use d) when I use the ? identifier?

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  • Using multiple aggregate functions in an (ANSI) SQL statement

    - by morpheous
    I have aggregate functions foo(), foobar(), fredstats(), barneystats() I want to create a domain specific query language (DSQL) above my DB, to facilitate using a domain language to query the DB. The 'language' comprises of algebraic expressions (or more specifically SQL like criteria) which I use to generate (ANSI) SQL statements which are sent to the db engine. The following lines are examples of what the language statements will look like, and hopefully, it will help further clarify the concept: **Example 1** DQL statement: foobar('yellow') between 1 and 3 and fredstats('weight') > 42 Translation: fetch all rows in an underlying table where computed values for aggregate function foobar() is between 1 and 3 AND computed value for AGG FUNC fredstats() is greater than 42 **Example 2** DQL statement: fredstats('weight') < barneystats('weight') AND foo('fighter') in (9,10,11) AND foobar('green') <> 42 Translation: Fetch all rows where the specified criteria matches **Example 3** DQL statement: foobar('green') / foobar('red') <> 42 Translation: Fetch all rows where the specified criteria matches **Example 4** DQL statement: foobar('green') - foobar('red') >= 42 Translation: Fetch all rows where the specified criteria matches Given the following information: The table upon which the queries above are being executed is called 'tbl' table 'tbl' has the following structure (id int, name varchar(32), weight float) The result set returns only the tbl.id, tbl.name and the names of the aggregate functions as columns in the result set - so for example the foobar() AGG FUNC column will be called foobar in the result set. So for example, the first DQL query will return a result set with the following columns: id, name, foobar, fredstats Given the above, my questions then are: What would be the underlying SQL required for Example1 ? What would be the underlying SQL required for Example3 ? Given an algebraic equation comprising of AGGREGATE functions, Is there a way of generalizing the algorithm needed to generate the required ANSI SQL statement(s)? I am using PostgreSQL as the db, but I would prefer to use ANSI SQL wherever possible.

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  • Impact of ordering of correlated subqueries within a projection

    - by Michael Petito
    I'm noticing something a bit unexpected with how SQL Server (SQL Server 2008 in this case) treats correlated subqueries within a select statement. My assumption was that a query plan should not be affected by the mere order in which subqueries (or columns, for that matter) are written within the projection clause of the select statement. However, this does not appear to be the case. Consider the following two queries, which are identical except for the ordering of the subqueries within the CTE: --query 1: subquery for Color is second WITH vw AS ( SELECT p.[ID], (SELECT TOP(1) [FirstName] FROM [Preference] WHERE p.ID = ID AND [FirstName] IS NOT NULL ORDER BY [LastModified] DESC) [FirstName], (SELECT TOP(1) [Color] FROM [Preference] WHERE p.ID = ID AND [Color] IS NOT NULL ORDER BY [LastModified] DESC) [Color] FROM Person p ) SELECT ID, Color, FirstName FROM vw WHERE Color = 'Gray'; --query 2: subquery for Color is first WITH vw AS ( SELECT p.[ID], (SELECT TOP(1) [Color] FROM [Preference] WHERE p.ID = ID AND [Color] IS NOT NULL ORDER BY [LastModified] DESC) [Color], (SELECT TOP(1) [FirstName] FROM [Preference] WHERE p.ID = ID AND [FirstName] IS NOT NULL ORDER BY [LastModified] DESC) [FirstName] FROM Person p ) SELECT ID, Color, FirstName FROM vw WHERE Color = 'Gray'; If you look at the two query plans, you'll see that an outer join is used for each subquery and that the order of the joins is the same as the order the subqueries are written. There is a filter applied to the result of the outer join for color, to filter out rows where the color is not 'Gray'. (It's odd to me that SQL would use an outer join for the color subquery since I have a non-null constraint on the result of the color subquery, but OK.) Most of the rows are removed by the color filter. The result is that query 2 is significantly cheaper than query 1 because fewer rows are involved with the second join. All reasons for constructing such a statement aside, is this an expected behavior? Shouldn't SQL server opt to move the filter as early as possible in the query plan, regardless of the order the subqueries are written?

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  • What is the right way to make a new XMLHttpRequest from an RJS response in Ruby on Rails?

    - by Yuri Baranov
    I'm trying to come closer to a solution for the problem of my previous question. The scheme I would like to try is following: User requests an action from RoR controller. Action makes some database queries, makes some calculations, sets some session variable(s) and returns some RJS code as the response. This code could either update a progress bar and make another ajax request. display the final result (e.g. a chart grahic) if all the processing is finished The browser evaluates the javascript representation of the RJS. It may make another (recursive? Is recursion allowed at all?) request, or just display the result for the user. So, my question this time is: how can I embed a XMLHttpRequest call into rjs code properly? Some things I'd like to know are: Should I create a new thread to avoid stack overflow. What rails helpers (if any) should I use? Have anybody ever done something similar before on Rails or with other frameworks? Is my idea sane?

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  • SQL Server Search Proper Names Full Text Index vs LIKE + SOUNDEX

    - by Matthew Talbert
    I have a database of names of people that has (currently) 35 million rows. I need to know what is the best method for quickly searching these names. The current system (not designed by me), simply has the first and last name columns indexed and uses "LIKE" queries with the additional option of using SOUNDEX (though I'm not sure this is actually used much). Performance has always been a problem with this system, and so currently the searches are limited to 200 results (which still takes too long to run). So, I have a few questions: Does full text index work well for proper names? If so, what is the best way to query proper names? (CONTAINS, FREETEXT, etc) Is there some other system (like Lucene.net) that would be better? Just for reference, I'm using Fluent NHibernate for data access, so methods that work will with that will be preferred. I'm using SQL Server 2008 currently. EDIT I want to add that I'm very interested in solutions that will deal with things like commonly misspelled names, eg 'smythe', 'smith', as well as first names, eg 'tomas', 'thomas'. Query Plan |--Parallelism(Gather Streams) |--Nested Loops(Inner Join, OUTER REFERENCES:([testdb].[dbo].[Test].[Id], [Expr1004]) OPTIMIZED WITH UNORDERED PREFETCH) |--Hash Match(Inner Join, HASH:([testdb].[dbo].[Test].[Id])=([testdb].[dbo].[Test].[Id])) | |--Bitmap(HASH:([testdb].[dbo].[Test].[Id]), DEFINE:([Bitmap1003])) | | |--Parallelism(Repartition Streams, Hash Partitioning, PARTITION COLUMNS:([testdb].[dbo].[Test].[Id])) | | |--Index Seek(OBJECT:([testdb].[dbo].[Test].[IX_Test_LastName]), SEEK:([testdb].[dbo].[Test].[LastName] >= 'WHITDþ' AND [testdb].[dbo].[Test].[LastName] < 'WHITF'), WHERE:([testdb].[dbo].[Test].[LastName] like 'WHITE%') ORDERED FORWARD) | |--Parallelism(Repartition Streams, Hash Partitioning, PARTITION COLUMNS:([testdb].[dbo].[Test].[Id])) | |--Index Seek(OBJECT:([testdb].[dbo].[Test].[IX_Test_FirstName]), SEEK:([testdb].[dbo].[Test].[FirstName] >= 'THOMARþ' AND [testdb].[dbo].[Test].[FirstName] < 'THOMAT'), WHERE:([testdb].[dbo].[Test].[FirstName] like 'THOMAS%' AND PROBE([Bitmap1003],[testdb].[dbo].[Test].[Id],N'[IN ROW]')) ORDERED FORWARD) |--Clustered Index Seek(OBJECT:([testdb].[dbo].[Test].[PK__TEST__3214EC073B95D2F1]), SEEK:([testdb].[dbo].[Test].[Id]=[testdb].[dbo].[Test].[Id]) LOOKUP ORDERED FORWARD) SQL for above: SELECT * FROM testdb.dbo.Test WHERE LastName LIKE 'WHITE%' AND FirstName LIKE 'THOMAS%' Based on advice from Mitch, I created an index like this: CREATE INDEX IX_Test_Name_DOB ON Test (LastName ASC, FirstName ASC, BirthDate ASC) INCLUDE (and here I list the other columns) My searches are now incredibly fast for my typical search (last, first, and birth date).

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  • PHP5 : Applying a method from an extended class on an object from the original (parent) class.

    - by Glauber Rocha
    Hello, I'm trying to extend two native PHP5 classes (DOMDocument and DOMNode) to implement 2 methods (selectNodes and selectSingleNode) in order to make XPath queries easier. I thought it would be rather straighforward, but I'm stuck in a problem which I think is an OOP beginner's issue. class nDOMDocument extends DOMDocument { public function selectNodes($xpath){ $oxpath = new DOMXPath($this); return $oxpath->query($xpath); } public function selectSingleNode($xpath){ return $this->selectNodes($xpath)->item(0); } } Then I tried to do extend DOMNode to implement the same methods so I can perform an XPath query directly on a node: class nDOMNode extends DOMNode { public function selectNodes($xpath){ $oxpath = new DOMXPath($this->ownerDocument,$this); return $oxpath->query($xpath); } public function selectSingleNode($xpath){ return $this->selectNodes($xpath)->item(0); } } Now if I execute the following code (on an arbitrary XMLDocument): $xmlDoc = new nDOMDocument; $xmlDoc->loadXML(...some XML...); $node1 = $xmlDoc->selectSingleNode("//item[@id=2]"); $node2 = $node1->selectSingleNode("firstname"); The third line works and returns a DOMNode object $node1. However, the fourth line doesn't work because the selectSingleNode method belongs to the nDOMNode class, not DOMNode. So my question: is there a way at some point to "transform" the returned DOMNode object into a nDOMNode object? I feel I'm missing some essential point here and I'd greatly appreciate your help. (Sorry, this is a restatement of my question http://stackoverflow.com/questions/2573820/)

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  • How can I get a distinct list of elements in a hierarchical query?

    - by RenderIn
    I have a database table, with people identified by a name, a job and a city. I have a second table that contains a hierarchical representation of every job in the company in every city. Suppose I have 3 people in the people table: [name(PK),title,city] Jim, Salesman, Houston Jane, Associate Marketer, Chicago Bill, Cashier, New York And I have thousands of job type/location combinations in the job table, a sample of which follow. You can see the hierarchical relationship since parent_title is a foreign key to title: [title,city,pay,parent_title] Salesman, Houston, $50000, CEO Cashier, Houston, $25000 CEO, USA, $1000000 Associate Marketer, Chicago, $75000 Senior Marketer, Chicago, $125000 ..... The problem I'm having is that my Person table is a composite key, so I don't know how to structure the start with part of my query so that it starts with each of the three jobs in the cities I specified. I can execute three separate queries to get what I want, but this doesn't scale well. e.g.: select * from jobs start with city = (select city from people where name = 'Bill') and title = (select title from people where name = 'Bill') connect by prior parent_title = title UNION select * from jobs start with city = (select city from people where name = 'Jim') and title = (select title from people where name = 'Jim') connect by prior parent_title = title UNION select * from jobs start with city = (select city from people where name = 'Jane') and title = (select title from people where name = 'Jane') connect by prior parent_title = title How else can I get a distinct list (or I could wrap it with a distinct if not possible) of all the jobs which are above the three people I specified?

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  • Why does the page posts take so long?

    - by Olle
    Hi! I am having some problems with some page post backs that take a loooong time to execute. If I do a "appcmd list requests" I can get something like this: REQUEST "79000001800004e3" (url:POST /dir/file.aspx, time:87219 msec, client:xxx.xxx.xxx.xxx, stage:ExecuteRequestHandler, module:ManagedPipelineHandler) REQUEST "8600000080002f82" (url:POST /dir/file.aspx, time:61391 msec, client:xxx.xxx.xxx.xxx, stage:AcquireRequestState, module:Session) REQUEST "5e00010280000420" (url:POST /dir/file.aspx, time:21047 msec, client:xxx.xxx.xxx.xxx, stage:AcquireRequestState, module:Session) It's one particular file that causes the problem (dir/file.aspx in this case). It comes from the same IP-adress. And the first on is from ManagedPipelineHandler module and the two after that from Session module. I do not have any details about the web browser, or anything more about the client for that matter. I have looked for sql dead locks and did not find any. There are no long running sql queries at all. Do you have any idea of what can be the problem? Regards.

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  • Does DefaultAppPool run with special elevated privilegs on IIS?

    - by Leeks and Leaks
    I'm running a piece of code within a web page that queries the IIS metabase using ADSI. The code is as simple as this: DirectoryEntry iisNode = new DirectoryEntry("/LM/W3SVC/1/ROOT/MyAspWebsite-1-128886021498831845"); foreach (DirectoryEntry de in iisNode.Parent.Children) { System.Console.WriteLine(de.Name); } This works fine when I run the page/site under the DefaultAppPool on IIS7/W2K8. However when I create my own app pool and leave the properties the same as the default app pool, this code fails with the following error: Caught: System.Runtime.InteropServices.COMException Failed to parse virtual directory: /LM/W3SVC/1/ROOT/MyAspWebsite-1-128889542757187500 System.Runtime.InteropServices.COMException (0x80070005): Access is denied. What special privileges does the DefaultAppPool have? I don't see any documented. I need this to work in non default app pools, but without giving the entire worker process elevated privileges. I've also tried using the username and password parameters of the DirectoryEntry constructor, by using the Admin on the machine that IIS7 is running on, but that didn't change anything. I'll also note that this works fine on IIS6 and W2K3. Any help is appreciated.

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  • PHP Performance Metrics

    - by bigstylee
    I am currently developing a PHP MVC Framework for a personal project. While I am developing the framework I am interested to see any notable performance by implementing different techniques for optimization. I have implemented a crude BenchMark class that logs mircotime. The problem is I have no frame of reference for execution times. I am very near the beginnig of this project with a database connection and a few queries but no output (bar some debugging text and BenchMark log). I have a current execution time of 0.01917 seconds. I was expecting this to be lower but as I said before I have no frame of reference. I appreciate there are many variables to take into account when juding performance but I am hoping to find some sort of metric to a) techniques to measure performance for example requests per second and b) compare results for example; how a "moderately" sized PHP application on a "standard" webserver will perform. I appreciate "moderately" and "standard" are very subjective words so perhaps a table of known execution times for a particular application (eg StackOverFlow's executing time). What are other techniques of measuring performance are there other than execution time? When looking at MVC Framework Performance Comparisom it talks about Requests Per Second (RPS). How is this calculated? I am guessing with my current execution time of 0.01917 seconds can handle 52 RPS (= 1 / 0.01917 ). This seems to be significantly lower than that quoted on the graph especially when you consider my current limited funcitonality.

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  • Use the repository pattern when using PLINQO generated data?

    - by Chad
    I'm "upgrading" an MVC app. Previously, the DAL was a part of the Model, as a series of repositories (based on the entity name) using standard LINQ to SQL queries. Now, it's a separate project and is generated using PLINQO. Since PLINQO generates query extensions based on the properties of the entity, I started using them directly in my controller... and eliminated the repositories all together. It's working fine, this is more a question to draw upon your experience, should I continue down this path or should I rebuild the repositories (using PLINQO as the DAL within the repository files)? One benefit of just using the PLINQO generated data context is that when I need DB access, I just make one reference to the the data context. Under the repository pattern, I had to reference each repository when I needed data access, sometimes needing to reference multiple repositories on a single controller. The big benefit I saw on the repositories, were aptly named query methods (i.e. FindAllProductsByCategoryId(int id), etc...). With the PLINQO code, it's _db.Product.ByCatId(int id) - which isn't too bad either. I like both, but where it gets "harrier" is when the query uses predicates. I can roll that up into the repository query method. But on the PLINQO code, it would be something like _db.Product.Where(x = x.CatId == 1 && x.OrderId == 1); I'm not so sure I like having code like that in my controllers. Whats your take on this?

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  • Combining SQL Rows

    - by lumberjack4
    I've got SQL Compact Database that contains a table of IP Packet Headers. The Table looks like this: Table: PacketHeaders ID SrcAddress SrcPort DestAddress DestPort Bytes 1 10.0.25.1 255 10.0.25.50 500 64 2 10.0.25.50 500 10.0.25.1 255 80 3 10.0.25.50 500 10.0.25.1 255 16 4 75.48.0.25 387 74.26.9.40 198 72 5 74.26.9.40 198 75.48.0.25 387 64 6 10.0.25.1 255 10.0.25.50 500 48 I need to perform a query to show 'conversations' going on across a local network. Packets going from A - B is part of the same conversations as packets going from B - A. I need to perform a query to show the on going conversations. Basically what I need is something that looks like this: Returned Query: SrcAddress SrcPort DestAddress DestPort TotalBytes BytesA->B BytesB->A 10.0.25.1 255 10.0.25.50 500 208 112 96 75.48.0.25 387 74.26.9.40 198 136 72 64 As you can see I need the query (or series of queries) to recognize that A-B is the same as B-A and break up the byte counts accordingly. I'm not a SQL guru by any means but any help on this would be greatly appreciated.

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  • Linq to XML Document Traversal

    - by Perpetualcoder
    I have an xml document like this: <?xml version="1.0" encoding="utf-8" ?> <demographics> <country id="1" value="USA"> <state id ="1" value="California"> <city>Long Beach</city> <city>Los Angeles</city> <city>San Diego</city> </state> <state id ="2" value="Arizona"> <city>Tucson</city> <city>Phoenix</city> <city>Tempe</city> </state> </country> <country id="2" value="Mexico"> <state id ="1" value="Baja California"> <city>Tijuana</city> <city>Rosarito</city> </state> </country> </demographics> How do I setup LINQ queries for doing things like: 1. Get All Countries 2. Get All States in a Country 3. Get All Cities inside a state of a paricular country ? I gave it a try and I am kind of confused when to use Elements["NodeName"] and Descendants etc. I know I am not the brightest XML guy around. Is the format of the XML file even correct for simple traversal?

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  • Need help choosing database server

    - by The Pretender
    Good day everyone. Recently I was given a task to develop an application to automate some aspects of stocks trading. While working on initial architecture, the database dilemma emerged. What I need is a fast database engine which can process huge amounts of data coming in very fast. I'm fairly experienced in general programming, but I never faced a task of developing a high-load database architecture. I developed a simple MSSQL database schema with several many-to-many relationships during one of my projects, but that's it. What I'm looking for is some advice on choosing the most suitable database engine and some pointers to various manuals or books which describe high-load database development. Specifics of the project are as follows: OS: Windows NT family (Server 2008 / 7) Primary platform: .NET with C# Database structure: one table to hold primary items and two or three tables with foreign keys to the first table to hold additional information. Database SELECT requirements: Need super-fast selection by foreign keys and by combination of foreign key and one of the columns (presumably DATETIME) Database INSERT requirements: The faster the better :) If there'll be significant performance gain, some parts can be written in C++ with managed interfaces to the rest of the system. So once again: given all that stuff I just typed, please give me some advice on what the best database for my project is. Links or references to some manuals and books on the subject are also greatly appreciated. EDIT: I'll need to insert 3-5 rows in 2 tables approximately once in 30-50 milliseconds and I'll need to do SELECT with 0-2 WHERE clauses queries with similar rate.

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  • AppEngine JDO-QL : Problem with multiple AND and OR in query

    - by KlasE
    Hi, I'm working with App Engine(Java/JDO) and are trying to do some querying with lists. So I have the following class: @PersistenceCapable(identityType = IdentityType.APPLICATION, detachable="true") public class MyEntity { @PrimaryKey @Persistent(valueStrategy = IdGeneratorStrategy.IDENTITY) Key key; @Persistent List<String> tags = new ArrayList<String>(); @Persistent String otherVar; } The following JDO-QL works for me: ( tags.contains('a') || tags.contains('b') || tags.contains('c') || tags.contains('d') ) && otherVar > 'a' && otherVar < 'z' This seem to return all results where tags has one or more strings with one or more of the given values and together with the inequality search on otherVar But the following do not work: (tags.contains('a') || tags.contains('_a')) && (tags.contains('b') || tags.contains('_b')) && otherVar > 'a' && otherVar < 'z' In this case I want all hits where there is at least one a (either a or _a) and one b (either b or _b) together with the inequality search as before. But the problem is that I also get back the results where there is a but no b, which is not what I want. Maybe I have missed something obvious, or done a coding error, or possibly there is a restriction on how you can write these queries in appengine, so any tips or help would be very welcome. Regards Klas

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  • Why use SQL database?

    - by martinthenext
    I'm not quite sure stackoverflow is a place for such a general question, but let's give it a try. Being exposed to the need of storing application data somewhere, I've always used MySQL or sqlite, just because it's always done like that. As it seems like the whole world is using these databases, most of all software products, frameworks, etc. It is rather hard for a beginning developer like me to ask a question - why? Ok, say we have some object-oriented logic in our application, and objects are related to each other somehow. We need to map this logic to the storage logic, so we need relations between database objects too. This leads us to using relational database and I'm ok with that - to put it simple, our database rows sometimes will need to have references to other tables' rows. But why do use SQL language for interaction with such a database? SQL query is a text message. I can understand this is cool for actually understanding what it does, but isn't it silly to use text table and column names for a part of application that no one ever seen after deploynment? If you had to write a data storage from scratch, you would have never used this kind of solution. Personally, I would have used some 'compiled db query' bytecode, that would be assembled once inside a client application and passed to the database. And it surely would name tables and colons by id numbers, not ascii-strings. In the case of changes in table structure those byte queries could be recompiled according to new db schema, stored in XML or something like that. What are the problems of my idea? Is there any reason for me not to write it myself and to use SQL database instead?

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  • rapid application developement tools for very basic GUI apps

    - by Jurij
    I know there are many RAD platforms out there. Infact there are so many that I'm having a hard time finding out which one fits me best. What I want is a RAD tool that would allow me to define a database data model (make DB tables) and then create (view and edit) forms for the various tables. Data input, updating and various queries should be easy and GUI should generate automatically. I'd like to add some additional functionality by coding (such as various complex calculations on the data). I'm a programmer so I'm willing to learn to use a more complete, full-blown RAD solution if you can point me to it (NetBeans and RubyOnRails being the two such frameworks that I'd would probably be high on the list). I'm currently doing Windows Forms logistics apps in .NET. I've actually developed a very crude and basic version of what I need, but I just know that there are solutions out there that are much better and I'd benefit by knowing how to use them. So in short, the basic requirements: * database based data storage (SQLite if possible) * very automated GUI creation * desktop based (as in: not a web app) * extendable by coding * used for creating simple data entry, view & query apps. So basically something like Oracle Forms or DotNetMushroom Rapid Application Developer. But for .NET and SQLite if possible.

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  • Database Design Question regaurding duplicate information.

    - by galford13x
    I have a database that contains a history of product sales. For example the following table CREATE TABLE SalesHistoryTable ( OrderID, // Order Number Unique to all orders ProductID, // Product ID can be used as a Key to look up product info in another table Price, // Price of the product per unit at the time of the order Quantity, // quantity of the product for the order Total, // total cost of the order for the product. (Price * Quantity) Date, // Date of the order StoreID, // The store that created the Order PRIMARY KEY(OrderID)); The table will eventually have millions of transactions. From this, profiles can be created for products in different geographical regions (based on the StoreID). Creating these profiles can be very time consuming as a database query. For example. SELECT ProductID, StoreID, SUM(Total) AS Total, SUM(Quantity) QTY, SUM(Total)/SUM(Quantity) AS AvgPrice FROM SalesHistoryTable GROUP BY ProductID, StoreID; The above query could be used to get the Information based on products for any particular store. You could then determine which store has sold the most, has made the most money, and on average sells for the most/least. This would be very costly to use as a normal query run anytime. What are some design descisions in order to allow these types of queries to run faster assuming storage size isn’t an issue. For example, I could create another Table with duplicate information. Store ID (Key), Product ID, TotalCost, QTY, AvgPrice And provide a trigger so that when a new order is received, the entry for that store is updated in a new table. The cost for the update is almost nothing. What should be considered when given the above scenario?

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  • Accessing Unicode telugu text from Ms-Access Database in Java

    - by Ravi Chandra
    I have an MS-Access database ( A English-telugu Dictionary database) which contains a table storing English words and telugu meanings. I am writing a dictionary program in Java which queries the database for a keyword entered by the user and display the telugu meaning. My Program is working fine till I get the data from the database, but when I displayed it on some component like JTextArea/JEditorPane/ etc... the telugu text is being displayed as '????'. Why is it happening?. I have seen the solution for "1467412/reading-unicode-data-from-an-access-database-using-jdbc" which provides some workaround for Hebrew language. But it is not working for telugu. i.e I included setCharset("UTF8")before querying from the database. but still I am getting all '?'s. As soon as I got data from Resultset I am checking the individual characters, all the telugu characters are being encoded by 63 only. This is my observation. I guess this must be some type of encoding problem. I would be very glad if somebody provides some solution for this. Thanks in advance.

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  • Way to automate setting of MergeOptions

    - by Nix
    I am looking for an automated way to iterate over all ObjectQueries and set the merge option to no tracking (read only context). Once i find out how to do it i will be able to generate a default read only context using a T4 template. Is this possible? For example lets say i have these tables in my object context SampleContext TableA TableB TableC I would have to go through and do the below. SampleContext sc = new SampleContext(); sc.TableA.MergeOption = MergeOption.NoTracking; sc.TableB.MergeOption = MergeOption.NoTracking; sc.TableC.MergeOption = MergeOption.NoTracking; I am trying to find a way to generalize this using object context. I want to get it down to something like foreach(var objectQuery : sc){ objectQuery.MergeOption = MergeOption.NoTracking; } Preferably I would like to do it using the baseclass(ObjectContext): ObjectContext baseClass = sc as ObjectContext var objectQueries = sc.MetadataWorkspace.GetItem("Magic Object Query Option); But i am not sure i can even get access to the queries. Any help would be appreciated.

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  • Does WPF break an Entity Framework ObjectContext?

    - by David Veeneman
    I am getting started with Entity Framework 4, and I am getting ready to write a WPF demo app to learn EF4 better. My LINQ queries return IQueryable<T>, and I know I can drop those into an ObservableCollection<T> with the following code: IQueryable<Foo> fooList = from f in Foo orderby f.Title select f; var observableFooList = new ObservableCollection<Foo>(fooList); At that point, I can set the appropriate property on my view model to the observable collection, and I will get WPF data binding between the view and the view model property. Here is my question: Do I break the ObjectContext when I move my foo list to the observable collection? Or put another way, assuming I am otherwise handling my ObjectContext properly, will EF4 properly update the model (and the database)? The reason why I ask is this: NHibernate tracks objects at the collection level. If I move an NHibernate IList<T> to an observable collection, it breaks NHibernate's change tracking mechanism. That means I have to do some very complicated object wrapping to get NHibernate to work with WPF. I am looking at EF4 as a way to dispense with all that. So, to get EF4 working with WPF, is it as simple as dropping my IQueryable<T> results into an ObservableCollection<T>. Does that preserve change-tracking on my EDM entity objects? Thanks for your help.

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  • Grails - Recursive computing call "StackOverflowError" and don't update on show

    - by Kedare
    Hello, I have a little problem, I have made a Category domain on Grails, but I want to "cache" the string representation on the database by generating it when the representation field is empty or NULL (to avoid recursive queries at each toString), here is the code : package devkedare class Category { String title; String description; String representation; Date dateCreated; Date lastUpdate; Category parent; static constraints = { title(blank:false, nullable:false, size:2..100); description(blank:true, nullable:false); dateCreated(nullable:true); lastUpdate(nullable:true); autoTimestamp: true; } static hasMany = [childs:Category] @Override String toString() { if((!this.representation) || (this.representation == "")) { this.computeRepresentation(true) } return this.representation; } String computeRepresentation(boolean updateChilds) { if(updateChilds) { for(child in this.childs) { child.representation = child.computeRepresentation(true); } } if(this.parent) { this.representation = "${this.parent.computeRepresentation(false)}/${this.title}"; } else { this.representation = this.title } return this.representation; } void beforeUpdate() { this.computeRepresentation(true); } } There is 2 problems : It don't update the representation when the representation if NULL or empty and toString id called, it only update it on save, how to fix that ? On some category, updating it throw a StackOverflowError, here is an example of my actual category table as CSV : Uploaded the csv file here, pasting csv looks buggy: http://kedare.free.fr/Dist/01.csv Updating the representation works everywhere except on "IT" that throw a StackOverlowError (this is the only category that has many childs). Any idea of how can I fix those 2 problems ? Thank you !

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  • Top 10 collection completion - a monster in-query formula in MySQL?

    - by Andrew Heath
    I've got the following tables: User Basic Data (unique) [userid] [name] [etc] User Collection (one to one) [userid] [game] User Recorded Plays (many to many) [userid] [game] [scenario] [etc] Game Basic Data (unique) [game] [total_scenarios] I would like to output a table that shows the collection play completion percentage for the Top 10 users in descending order of %: Output Table [userid] [collection_completion] 3 95% 1 81% 24 68% etc etc In my mind, the calculation sequence for ONE USER is: grab user's total owned scenarios from User Collection joined with Game Basic Data and COUNT(gbd.total_scenarios) grab all recorded plays by COUNT(DISTINCT scenario) for that user Divide all recorded plays by total owned scenarios So that's 2 queries and a little PHP massage at the end. For a list of users sorted by completion percentage things get a little more complicated. I figure I could grab all users' collection totals in one query, and all users recorded plays in another, and then do the calcs and sort the final array in PHP, but it seems like overkill to potentially be doing all that for 1000+ users when I only ever want the Top 10. Is there a wicked monster query in MySQL that could do all that and LIMIT 10? Or is sticking with PHP handling the bulk of the work the way to go in this case?

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  • Delphi Application using COMMIT and ROLLBACK for Multiple SQL Updates

    - by Matt
    Is it possible to use the SQL BEGIN TRANSACTION, COMMIT TRANSACTION, ROLLBACK TRANSACTION when embedding SQL Queries into an application with mutiple calls to the SQL for Table Updates. For example I have the following code: Q.SQL.ADD(<UPDATE A RECORD>); Q.ExecSQL; Q.Close; Q.SQL.Clear; Q.SQL.ADD(<Select Some Data>); Q.Open; Set Some Variables Q.Close; Q.SQL.Clear; Q.SQL.ADD(<UPDATE A RECORD>); Q.ExecSQL; What I would like to do is if the second update fails I want to roll back the first transaction. If I set a unique notation for the BEGIN, COMMIT, ROLLBACK so as to specify what is being committed or rolled back, is it feasible. i.e. before the first Update specify BEGIN TRANSACTION_A then after the last update specify COMMIT TRANSACTION_A I hope that makes sense. If I was doing this in a SQL Stored Procedure then I would be able to specify this at the start and end of the procedure, but I have had to break the code down into manageable chunks due to process blocks and deadlocks on a heavy loaded SQL Server.

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  • Using LINQ to SQL and chained Replace

    - by White Dragon
    I have a need to replace multiple strings with others in a query from p in dx.Table where p.Field.Replace("A", "a").Replace("B", "b").ToLower() = SomeVar select p Which provides a nice single SQL statement with the relevant REPLACE() sql commands. All good :) I need to do this in a few queries around the application... So i'm looking for some help in this regard; that will work as above as a single SQL hit/command on the server It seems from looking around i can't use RegEx as there is no SQL eq Being a LINQ newbie is there a nice way for me to do this? eg is it possible to get it as a IQueryable "var result" say and pass that to a function to add needed .Replace()'s and pass back? Can i get a quick example of how if so? EDIT: This seems to work! does it look like it would be a problem? var data = from p in dx.Videos select p; data = AddReplacements(data, checkMediaItem); theitem = data.FirstOrDefault(); ... public IQueryable<Video> AddReplacements(IQueryable<Video> DataSet, string checkMediaItem) { return DataSet.Where(p => p.Title.Replace(" ", "-").Replace("&", "-").Replace("?", "-") == checkMediaItem); }

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