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  • Export a SQL database into a CSV file and use it with WEKA

    - by Simon
    How can I export a query result from a .sql database into a .csv file? I tried with SELECT * FROM players INTO OUTFILE 'players.csv' FIELDS TERMINATED BY ',' LINES TERMINATED BY ';';` and my .csv file is something like: p1,1,2,3 p2,1,4,5 But they are not in saparated columns, all are in 1 column. I tried to create a .csv file by myself just to try WEKA, something like: p1 1 2 3 p2 1 4 5 But WEKA recognizes p1 1 2 3 as a single attribute. So: how can I export correctly a table from a sql db to a csv file? And how can I use it with WEKA?

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  • How to use parameter with LIKE in Sql Server Compact Edition

    - by Colin
    I'm trying to parameterise a search query that uses the LIKE keyword with a wildcard. The original sql has dynamic sql like this: "AND JOB_POSTCODE LIKE '" + isPostCode + "%' " So I've tried this instead, but I get a FormatException: "AND JOB_POSTCODE LIKE @postcode + '%' " Edit: I guess the FormatException isn't going to be coming from Sql Server CE, so as requested, here is how I set the parameter in my C# code. The parameter is set in code like this: command.Parameters.Add("@postcode", SqlDbType.NVarChar).Value = isPostCode; I also tried: "AND JOB_POSTCODE LIKE @postcode" with command.Parameters.Add("@postcode", SqlDbType.NVarChar).Value = isPostCode + "%"; but that doesn't return any results. Can anyone advise how to use parameters in this search sql?

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  • My presentation layer does not match my model layer even though I have no animations

    - by Kevin McCullough
    On iPhone I have a CALayer that I animate via Core Animation. Then at some point I change view controllers. I then return to the view controller with the CALayer and in viewWillAppear: I set the frame and position properties on my layer to move it back to its starting point. Setting these properties changes the model layer but the presentation layer still has the old values and its presentation layer does not update until the next animation I play. In the CA Programming guide it says "You can query an instance of CALayer for its corresponding presentation layer while an animation transaction is in process." Which, to me, implies that the presentation layer should only be different from the model layer during an animation. But there are no animations currently running. I even used kCATransactionDisableActions to ensure that when I set the position property an implicit animation is not started. Does anyone know why my presentation and model layers are out of sync? Thanks.

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  • Free Online tools for testing mysql queries - having features like PhPMyAdmin

    - by Sandeepan Nath
    Can anybody tell me any "free online hosted database servers" (don't know if that is the correct term) where we can do query testing and all those things that we can do on tools like PhpMyAdmin? does something like that exist? Like we have http://jsfiddle.net/ for testing js codes. I checked http://sqlzoo.net/ but this is very much limited and there are some predefined tables in some given examples on which we can alter things. That's all. It does not allow me to do a lots of other things like creating tables etc. A nice resource - PhpMyAdmin's demo site . Use the latest stable version here. You have full control over the MySQL server, however you should not change root, debian-sys-maint or pma user password or limit their permissions. If you do so, demo can not be accessed until privileges are restored, so you just break things for you and other users.

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  • SQL constructs translated to OOP

    - by python dude
    As someone who comes from the world of Object Orientation, I find it rather difficult to wrap my head around SQL. Recently, however, I realized that the classical SQL construct select X from Y where Z is basically equivalent to the following OOP construct: List<SomeType> results = db.query(new Matcher<SomeType> () { public boolean match(SomeType candidate) { return ...; // checks condition Z on candidate, returns true for match } }; So my question is: What are the OOP equivalents for other SQL constructs, such as joins?

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  • CodePlex Daily Summary for Saturday, March 03, 2012

    CodePlex Daily Summary for Saturday, March 03, 2012Popular ReleasesAcDown????? - Anime&Comic Downloader: AcDown????? v3.9.1: ?? ●AcDown??????????、??、??????,????1M,????,????,?????????????????????????。???????????Acfun、????(Bilibili)、??、??、YouTube、??、???、??????、SF????、????????????。??????AcPlay?????,??????、????????????????。 ● AcDown???????????????????????????,???,???????????????????。 ● AcDown???????C#??,????.NET Framework 2.0??。?????"Acfun?????"。 ????32??64? Windows XP/Vista/7/8 ????????????? ??:????????Windows XP???,?????????.NET Framework 2.0???(x86),?????"?????????"??? ??????????????,??????????: ??"AcDo...Windows Phone Commands for VS2010: Version 1.0: Initial Release Version 1.0 Connect from device or emulator (Monitors the connection) Show Device information (Plataform, build , version, avaliable memory, total memory, architeture Manager installed applications (Launch, uninstall and explorer isolate storage files) Manager core applications (Launch blocked applications from emulator (Office, Calculator, alarm, calendar , etc) Manager blocked settings from emulator (Airplane Mode, Celullar Network, Wifi, etc) Deploy and update ap...DNN Metro7 style Skin package: Metro7 style Skin for DotNetNuke 06.01.00: Changes on Version 06.01.00 Fixed issue on GraySmallTitle container, that breaks the layout Fixed issue on Blue Metro7 Skin where the Search, Login, Register, Date is missing Fixed issue with the Version numbers on the target file Fixed issue where the jQuery and jQuery-UI files not deleted on upgrade from Version 01.00.00 Added a internal page where the Image Slider would be replaces with a BannerPaneMedia Companion: MC 3.433b Release: General More GUI tweaks (mostly imperceptible!) Updates for mc_com.exe TV The 'Watched' button has been re-instigated Added TV Menu sub-option to search ALL for new Episodes (includes locked shows) Movies Added 'Source' field (eg DVD, Bluray, HDTV), customisable in Advanced Preferences (try it out, let us know how it works!) Added HTML <<format>> tag with optional parameters for video container, source, and resolution (updated HTML tags to be added to Documentation shortly) Known Issu...Picturethrill: Version 2.3.2.0: Release includes Self-Update feature for Picturethrill. What that means for users is that they are always guaranteed to have a fresh copy of Picturethrill on their computers with all latest fixes. When Picturethrill adds a new website to get pictures from, you will get it too!THE NVL Maker: The NVL Maker Ver 3.11: SIM??????,TRA??????, ????????????????,??????~(??????????????????) ??: 115?? ???? http://115.com/file/bewo7t11#THENVLMakerver3.11sim.zip MediaFire ???? http://www.mediafire.com/?wj9dmk3eb70mdzt 3.11 ??? ???: ·????????????UNICODE????????????????????(??Data.xp3) ·?????.?(https://sites.google.com/site/hiyuadv/) ?????????krkrcht.exe ·?????????Editor.exe,????????krkrcht.exe?? ??: ·Wizard.exe??,BUG??,?????????????? ·????(Code)???,???????????????, ·??3.10?,???????????????,?????????????? ...Simple MVVM Toolkit for Silverlight, WPF and Windows Phone: Simple MVVM Toolkit v3.0.0.0: Added support for Silverlight 5.0 and Windows Phone 7.1. Upgraded project templates and samples. Upgraded installer. There are some new prerequisites required for this version, namely Silverlight 5 Tools, Expression Blend Preview for Silverlight 5 (until the SDK is released), Windows Phone 7.1 SDK. Because it is in the experimental band, I have also removed the dependency on the Silverlight Testing Framework. You can use it if you wish, but the Ria Services project template no longer uses ...CODE Framework: 4.0.20301: The latest version adds a number of new features to the WPF system (such as stylable and testable messagebox support) as well as various new features throughout the system (especially in the Utilities namespace).WPF Sound Visualization Library: WPF SVL 0.3 (Source, Binaries, Examples, Help): Version 0.3 of WPFSVL. This includes three new controls: an equalizer, a digital clock, and a time editor.Cocktail: Cocktail v0.4: PrerequisitesVisual Studio 2010 with SP1 (any edition but Express) SQL Server Express (included automatically with most Visual Studio installs) Optional: Silverlight 4 or 5 Note: Install Silverlight 4 Tools and then the Silverlight 4 Toolkit. Likewise for Silverlight 5 Tools and the Silverlight 5 Toolkit DevForce Universal Express 6.1.6 or greater Included in the Cocktail download, DevForce Universal Express requires registration) Important: Install DevForce after all other compo...Orchard Project: Orchard 1.4: Please read our release notes for Orchard 1.4: http://docs.orchardproject.net/Documentation/Orchard-1-4-Release-NotesFluentData -Micro ORM with a fluent API that makes it simple to query a database: FluentData version 1.2: New features: - QueryValues method - Added support for automapping to enumerations (both int and string are supported). Fixed 2 reported issues.NetSqlAzMan - .NET SQL Authorization Manager: 3.6.0.15: 3.6.0.15 28-Feb-2012 • Fix: The communication object, System.ServiceModel.Channels.ServiceChannel, cannot be used for communication because it is in the Faulted state. Work Item 10435: http://netsqlazman.codeplex.com/workitem/10435 • Fix: Made StorageCache thread safe. Thanks to tangrl. • Fix: Members property of SqlAzManApplicationGroup is not functioning. Thanks to tangrl. Work Item 10267: http://netsqlazman.codeplex.com/workitem/10267 • Fix: Indexer are making database calls. Thanks to t...SCCM Client Actions Tool: Client Actions Tool v1.1: SCCM Client Actions Tool v1.1 is the latest version. It comes with following changes since last version: Added stop button to stop the ongoing process. Added action "Query update status". Added option "saveOnlineComputers" in config.ini to enable saving list of online computers from last session. Default value for "LatestClientVersion" set to SP2 R3 (4.00.6487.2157). Wuauserv service manual startup mode is considered healthy on Windows 7. Errors are now suppressed in checkReleases...Document.Editor: 2012.1: Whats new for Document.Editor 2012.1: Improved Recent Documents list Improved Insert Shape Improved Dialogs Minor Bug Fix's, improvements and speed upsASP.NET REST Services Framework: Release 1.1 - Standard version: Beginning from v1.1 the REST-services Framework is compatible with ASP.NET Routing model as well with CRUD (Create, Read, Update, and Delete) principle. These two are often important when building REST API functionality within your application. It also includes ability to apply Filters to a class to target all WebRest methods, as well as some performance enhancements. New version includes Metadata Explorer providing ability exploring the existing services that becomes essential as the number ...SQL Live Monitor: SQL Live Monitor 1.31: A quick fix to make it this version work with SQL 2012. Version 2 already has 2012 working, but am still developing the UI in version 2, so this is just an interim fix to allow user to monitor SQL 2012.DotNet.Highcharts: DotNet.Highcharts 1.1 with Examples: Fixed small bug in JsonSerializer about the numbers represented as string. Fixed Issue 310: decimal values don't work Fixed Issue 345: Disable Animation Refactored Highcharts class. Implemented Issue 341: More charts on one page. Added new class Container which can combine and display multiple charts. Usage: new Container(new[] { chart1, chart2, chart3, chart4 }) Implemented Feature 302: Inside an UpdatePanel - Added method (InFunction) which create the Highchart inside JavaScript f...Content Slider Module for DotNetNuke: 01.02.00: This release has the following updates and new features: Feature: One-Click Enabling of Pager Setting Feature: Cache Sliders for Performance Feature: Configurable Cache Setting Enhancement: Transitions can be Selected Bug: Secure Folder Images not Viewable Bug: Sliders Disappear on Postback Bug: Remote Images Cause Error Bug: Deleted Images Cause Error System Requirements DotNetNuke v06.00.00 or newer .Net Framework v3.5 SP1 or newer SQL Server 2005 or newerImage Resizer for Windows: Image Resizer 3 Preview 3: Here is yet another iteration toward what will eventually become Image Resizer 3. This release is stable. However, I'm calling it a preview since there are still many features I'd still like to add before calling it complete. Updated on February 28 to fix an issue with installing on multi-user machines. As usual, here is my progress report. Done Preview 3 Fix: 3206 3076 3077 5688 Fix: 7420 Fix: 7527 Fix: 7576 7612 Preview 2 6308 6309 Fix: 7339 Fix: 7357 Preview 1 UI...New Projectsbinbin pager: pager extensionCC&PPTK-VSN: CC&PPTK-VSN Thi?t l?p SVN di nhóm D16TPMCCG (Crud Class Generator): CCGDatamodel Manager: Datamodel Manager is tool for managing database part of application.Daun Management Studio: Daun Management Studio is a management tool that is used for configuring, managing, and administering all components within MongoDB. The tool includes both script editors and graphical tools which work with features of MongoDB.DotNetNuke Role-Based Control Panels: This provider extends the DotNetNuke control panel by allowing a host to specify the particular control panel that is to be loaded by role (and site). For non-administrators any user interface may be utilized, allowing for flexible custom functionality not otherwise possible.HTML Creator: HTML Creator allows a web designer/developer to concentrate on the design and development of their web project; not the mundane tasks of project development. HTML Creator will combine the development, testing, debugging, and publishing stages into a complete workflow. This project uses .NET 4 Framework, Visual Basic 2010, and WPF as the primary programming languages.Ibiiztera: 3D shapes and figures renderingiNavigate: Same jQuery autocomplete, but with more optionsMapUpdater: MapUpdater is a simple application that connects to one or more ftp servers, downloads your minecraft world data, generates images and uploads them to another ftp server. c10t is the only renderer currently supported.Minecraft Web Launcher: Minecraft Web Launcher detects attempts to use an incomplete Minecraft.net API and overrides it, allowing you to launch Minecraft from a web browser and go directly to a certain server.MS CRM 2011 - Orbis- Client Caching Tool: The purpose of this tool is to cache all or the top most aspx pages. Caching means that this tool tests the Microsoft Dynamics CRM Client offline setting. If the client is offline OrbCrmCC ensures in a defined interval that the MSCRM Client host is up and that the aspx files are Mushroom: A very nice tool for web developers for both client-side or server-side development. What I will do here is to turn my own development environment into a very easy-to-use gui application which will run on Windows, Linux, and MacOS. It will support different languages, frameworks, and databases. Mushroom will make individuals and teams work much more efficiently by doing all the drudgery automatically. By providing some standard ways of doing things, --of course without enforcing them, i...My NerdDinner for WP7: A sample OData app for Windows Phone 7.1 based on NerdDinner.com servicesNClassify: nclassifyRealAge: EN: Real Age a gadget / web page showing Your current age inclusive the leap days. Funny for birthday parties ! ES: Edad verdadero un gadget / página web calculando Tu edad verdadero actual incluido las días intercalares. Divertido para fiestas de cumpleaños! DE: Wahres Alter ein Gadget / eine Webseite das Dein wahres aktuelles Alter berechnet inklusive Schalttage. Lustig für Geburtstagsparties ! HTML, javascript, XMLSharpInteract: A library that aims at providing a more easy interface to a set of interaction tools.SL5 Basic Calculator (No Frill) ver 1.0: the project is a basic calculator control developed in Silverlight 5, feel free to include in your projects. However CODE is AS/IS without any guarantee and warantee . use at your own risk(Source code included.SlyLamb: We develop applications for Windows Phone 7. Here we place our open application examples.SQLinq - use LINQ to generate Ad-Hoc Sql Queries: Easily generate ad-hoc SQL code using LINQ in a strongly typed manner that allows for compile time validation of you sql scripts.SSamTV: LVTN2012WildSoft Own Project: Personal WildSoftware Own ProjectWP7 Weather: WP7 Weather shows weather from site weather.uaym2u: this is my portal for demo

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  • Prolog n00b question: Doing whatever

    - by dmindreader
    I want to load this simple something into my Editor: Write:-repeat,write("hi"),nl,fail. So that it prints "hi". What should I do? I'm currently trying to do File->New and Saving a file named Write into E:\Program Files\pl\xpce\prolog\lib When doing the query: ?-Write. It's printing: 1 ?- Write. % ... 1,000,000 ............ 10,000,000 years later % % >> 42 << (last release gives the question) Why?

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  • SQL Average Data Based on Distance

    - by jsmith
    I'm pretty new to SQL. I have a database with records based on road/milepoints. My goal is to get an average value every 52.8 ft along the road. My related table has data every 15 ft, this table of course has a foreign key relating it to the primary table. If I wanted to pull out the average value every 52.8 ft, along a given milepost, how would I go about this? Example Data: RecID Begin_MP End_MP 100 0 0.56 RecID MP Value1 Value2 100 0 159 127.7 100 0.003 95.3 115.3 100 0.006 82.3 107 100 0.009 56.5 74.5 100 0.011 58.1 89.1 100 0.014 95.2 78.8 100 0.017 108.9 242.5 100 0.02 71.8 73.3 100 0.023 84.1 80.2 100 0.026 65.5 66.1 100 0.028 122 135.8 100 0.031 99.9 230.7 100 0.034 95.7 111.5 100 0.037 127.3 74.3 100 0.04 140.7 543.1 The first Data is an example of a Road. The second subset of data are the values I need to query out every 52.8 ft. Thank you

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  • Select dynamic string has a different value when referenced in Where clause

    - by David
    I dynamically select a string built using another string. So, if string1='David Banner', then MyDynamicString should be 'DBanne' Select ... , Left( left((select top 1 strval from dbo.SPLIT(string1,' ')) //first word ,1) //first character + (select top 1 strval from dbo.SPLIT(string1,' ') //second word where strval not in (select top 1 strval from dbo.SPLIT(string1,' '))) ,6) //1st character of 1st word, followed by up to 5 characters of second word [MyDynamicString] ,... From table1 Join table2 on table1pkey=table2fkey Where MyDynamicString <> table2.someotherfield I know table2.someotherfield is not equal to the dynamic string. However, when I replace MyDynamicString in the Where clause with the full left(left(etc.. function, it works as expected. Can I not reference this string later in the query? Do I have to build it using the left(left(etc.. function each time in the where clause?

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  • Finding duplicate values in a SQL table - ADVANCED

    - by Alex
    It's easy to find duplicates with one field SELECT name, COUNT(email) FROM users GROUP BY email HAVING ( COUNT(email) > 1 ) So if we have a table ID NAME EMAIL 1 John [email protected] 2 Sam [email protected] 3 Tom [email protected] 4 Bob [email protected] 5 Tom [email protected] This query will give us John, Sam, Tom, Tom because they all have the same e-mails. But what I want, is to get duplicates with the same e-mails and names. I want to get Tom, Tom. I made a mistake, and allowed to insert duplicate name and e-mail values. Now I need to remove/change the duplicates. But I need to find them first.

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  • How to use MySql date_add in Nhibernate?

    - by jalchr
    This really puzzled for hours, I searched all over the internet, but got no working solution. Can someone point where the problem is ... thanks ! I created my own dialect class public class MySQLDialectExtended : MySQLDialect { public MySQLDialectExtended() { RegisterFunction("date_add_interval", new SQLFunctionTemplate(NHibernateUtil.Date, "date_add(?1, INTERVAL ?2 ?3)")); } } Then I try to use it as follows: query.Append( " ( date_add_interval(D.ApprovalDate, 1, YEAR) < current_timestamp() < date_add_interval(D.RenewalDate, -1, YEAR) )"); It fails with following exception: NHibernate.Hql.Ast.ANTLR.QuerySyntaxException : Exception of type 'Antlr.Runtime.NoViableAltException' was thrown. near line 1, column 677 where the column number is at the end of the first 'YEAR' word. Edit: here is my configuration <property name="dialect">MyCompanyName.MySQLDialectExtended, MyCompanyName</property> <property name="hbm2ddl.keywords">none</property>

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  • Probability distribution for sms answer delays

    - by Thomas Ahle
    I'm writing an app using sms as communication. I have chosen to subscribe to an sms-gateway, which provides me with an API for doing so. The API has functions for sending as well as pulling new messages. It does however not have any kind of push functionality. In order to do my queries most efficient, I'm seeking data on how long time people wait before they answer a text message - as a probability function. Extra info: The application is interactive (as can be), so I suppose the times will be pretty similar to real life human-human communication. I don't believe differences in personal style will play a big impact on the right times and frequencies to query, so average data should be fine.

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  • Inverted index in a search engine

    - by Ayman
    Hello there, I'm trying to write some code to make a small application for searching text from files. Files should be crawled, and I need to put an inverted index to boost searches. My problem is that I kind of have ideas about how the parser would be, I'm willing to implement the AND, NOT, OR in the query. Whereas, I couldn't figure out how my index should be... I have never created an inverted index so if any body could suggest a feasable way to do it I would be very grateful... I do know in theory how it works but my problem is I absolutely have no idea to make happen in MySql I need to give keywords being indexed a weight too... Thank you so much.

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  • How to keep a process running on a remote windows server

    - by DutrowLLC
    I need to implement a background process that runs on a remote windows server 24/7. My development environment is C#/ASP.NET 3.5. The purpose of the process is to: Send reminder e-mails to employees and customers at appropriate times (say 5:00PM on the day before a job is scheduled) Query and save GPS coordinates of employees when they are supposed to be out on jobs so that I can later verify that their positions were where they were supposed to be. If the process fails (which it probably will, especially when updates are added), I need for it to be restarted immediately (or within just a few minutes) as I would have very serious problems if this process failed to send a notification, log a GPS coordinate, or any of the other tasks its meant to perform.

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  • Why does an event handler never get called if it's added within a loop on an ienumerable?

    - by André Carvalho
    Why does an event handler never get called if it's added within a loop on an ienumerable? For instance: IEnumerable<MyType> list = someCollection.Select(i => new MyType(i)); foreach (var item in list) item.PropertyChanged += item_PropertyChanged; <-- this never gets called Bu if list is assigned like list = someCollection.Select(i => new MyType(i)).ToArray(); the event handler does get called.. Why? (I imagine it has something to do with the fact that a LINQ query is lazy, but the fact of looping through the result isn't enough?)

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  • How do I memoize expensive calculations on Django model objects?

    - by David Eyk
    I have several TextField columns on my UserProfile object which contain JSON objects. I've also defined a setter/getter property for each column which encapsulates the logic for serializing and deserializing the JSON into python datastructures. The nature of this data ensures that it will be accessed many times by view and template logic within a single Request. To save on deserialization costs, I would like to memoize the python datastructures on read, invalidating on direct write to the property or save signal from the model object. Where/How do I store the memo? I'm nervous about using instance variables, as I don't understand the magic behind how any particular UserProfile is instantiated by a query. Is __init__ safe to use, or do I need to check the existence of the memo attribute via hasattr() at each read? Here's an example of my current implementation: class UserProfile(Model): text_json = models.TextField(default=text_defaults) @property def text(self): if not hasattr(self, "text_memo"): self.text_memo = None self.text_memo = self.text_memo or simplejson.loads(self.text_json) return self.text_memo @text.setter def text(self, value=None): self.text_memo = None self.text_json = simplejson.dumps(value)

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  • How to remove my backslash while input have underscore

    - by bob
    Problem when I enter any input which has underscore (_) data will store to my db looks like this image\_background.png Example $image = stripslashes($_POST['image']); // example image name image_background.png $query = 'UPDATE product SET image="' . $db->string_escape($image, true) . '" WHERE id="' . intval($id) . '"'; The problem coming when input has underscore only. If without underscore all backslashes will remove by the stripslashes Let me know.

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  • What should I do with syncobj in SQL Server

    - by hgulyan
    Hi. I run this script to search particular text in sys.columns and I get a lot of "dbo.syncobj_0x3934443438443332" this kind of result. SELECT c.name, s.name + '.' + o.name FROM sys.columns c INNER JOIN sys.objects o ON c.object_id=o.object_id INNER JOIN sys.schemas s ON o.schema_id=s.schema_id WHERE c.name LIKE '%text%' If I get it right, they are replication objects. Is it so? Can i just throw them away from my query just like o.name NOT LIKE '%syncobj%' or there's another way? Thank you.

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  • Mutating the expression tree of a predicate to target another type

    - by Jon
    Intro In the application I 'm currently working on, there are two kinds of each business object: the "ActiveRecord" type, and the "DataContract" type. So for example, we have: namespace ActiveRecord { class Widget { public int Id { get; set; } } } namespace DataContracts { class Widget { public int Id { get; set; } } } The database access layer takes care of "translating" between hierarchies: you can tell it to update a DataContracts.Widget, and it will magically create an ActiveRecord.Widget with the same property values and save that. The problem I have surfaced when attempting to refactor this database access layer. The Problem I want to add methods like the following to the database access layer: // Widget is DataContract.Widget interface DbAccessLayer { IEnumerable<Widget> GetMany(Expression<Func<Widget, bool>> predicate); } The above is a simple general-use "get" method with custom predicate. The only point of interest is that I 'm not passing in an anonymous function but rather an expression tree. This is done because inside DbAccessLayer we have to query ActiveRecord.Widget efficiently (LINQ to SQL) and not have the database return all ActiveRecord.Widget instances and then filter the enumerable collection. We need to pass in an expression tree, so we ask for one as the parameter for GetMany. The snag: the parameter we have needs to be magically transformed from an Expression<Func<DataContract.Widget, bool>> to an Expression<Func<ActiveRecord.Widget, bool>>. This is where I haven't managed to pull it off... Attempted Solution What we 'd like to do inside GetMany is: IEnumerable<DataContract.Widget> GetMany( Expression<Func<DataContract.Widget, bool>> predicate) { var lambda = Expression.Lambda<Func<ActiveRecord.Widget, bool>>( predicate.Body, predicate.Parameters); // use lambda to query ActiveRecord.Widget and return some value } This won't work because in a typical scenario, for example if: predicate == w => w.Id == 0; ...the expression tree contains a MemberAccessExpression instance which has a MemberInfo property (named Member) that point to members of DataContract.Widget. There are also ParameterExpression instances both in the expression tree and in its parameter expression collection (predicate.Parameters); After searching a bit, I found System.Linq.Expressions.ExpressionVisitor (its source can be found here in the context of a how-to, very helpful) which is a convenient way to modify an expression tree. Armed with this, I implemented a visitor. This simple visitor only takes care of changing the types in member access and parameter expressions. It may not be complete, but it's fine for the expression w => w.Id == 0. internal class Visitor : ExpressionVisitor { private readonly Func<Type, Type> dataContractToActiveRecordTypeConverter; public Visitor(Func<Type, Type> dataContractToActiveRecordTypeConverter) { this.dataContractToActiveRecordTypeConverter = dataContractToActiveRecordTypeConverter; } protected override Expression VisitMember(MemberExpression node) { var dataContractType = node.Member.ReflectedType; var activeRecordType = this.dataContractToActiveRecordTypeConverter(dataContractType); var converted = Expression.MakeMemberAccess( base.Visit(node.Expression), activeRecordType.GetProperty(node.Member.Name)); return converted; } protected override Expression VisitParameter(ParameterExpression node) { var dataContractType = node.Type; var activeRecordType = this.dataContractToActiveRecordTypeConverter(dataContractType); return Expression.Parameter(activeRecordType, node.Name); } } With this visitor, GetMany becomes: IEnumerable<DataContract.Widget> GetMany( Expression<Func<DataContract.Widget, bool>> predicate) { var visitor = new Visitor(...); var lambda = Expression.Lambda<Func<ActiveRecord.Widget, bool>>( visitor.Visit(predicate.Body), predicate.Parameters.Select(p => visitor.Visit(p)); var widgets = ActiveRecord.Widget.Repository().Where(lambda); // This is just for reference, see below Expression<Func<ActiveRecord.Widget, bool>> referenceLambda = w => w.Id == 0; // Here we 'd convert the widgets to instances of DataContract.Widget and // return them -- this has nothing to do with the question though. } Results The good news is that lambda is constructed just fine. The bad news is that it isn't working; it's blowing up on me when I try to use it (the exception messages are really not helpful at all). I have examined the lambda my code produces and a hardcoded lambda with the same expression; they look exactly the same. I spent hours in the debugger trying to find some difference, but I can't. When predicate is w => w.Id == 0, lambda looks exactly like referenceLambda. But the latter works with e.g. IQueryable<T>.Where, while the former does not (I have tried this in the immediate window of the debugger). I should also mention that when predicate is w => true, it all works just fine. Therefore I am assuming that I 'm not doing enough work in Visitor, but I can't find any more leads to follow on. Can someone point me in the right direction? Thanks in advance for your help!

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  • Update DataBase on clicking in button, after editing gridview (not automatically saving in DB, but a

    - by gaponte69
    0 vote down star I am using GridView in asp .net and editing data with edit command field property (as we know after updating the edited row, we automatically update the database), and I want to use transactions (with begin to commit statement - including rollback) to commit this update query in database, after clicking in some button (after some events for example), not automatically to insert or update the edited data from grid directly to the DB...so I want to save them somewhere temporary (even many edited rows - not just one row) and then to confirm the transaction - to update the real tables in database... Any suggestions are welcomed... I've used some good links, but very helpful, like: http://www.asp.net/learn/data-access/tutorial-63-cs.aspx http://www.asp.net/learn/data-access/tutorial-66-cs.aspx etc... etc...

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  • storing data in a database using edit text and button

    - by user1841444
    Hai im trying to Insert data into database using EditText and Button i have created. Im stuck at Activity part of the Code.I unbale to proceed how to write the Onclick action part for Button and EditText part Please help me. Im new to android DBAdapter.java package com.example.database1; import android.content.ContentValues; import android.content.Context; import android.database.Cursor; import android.database.SQLException; import android.database.sqlite.SQLiteDatabase; import android.database.sqlite.SQLiteOpenHelper; import android.util.Log; public class DBAdapter { public static final String KEY_ROWID = "_id"; public static final String KEY_ISBN = "isbn"; public static final String KEY_TITLE = "title"; public static final String KEY_PUBLISHER = "publisher"; private static final String TAG = "DBAdapter"; private static final String DATABASE_NAME = "books"; private static final String DATABASE_TABLE = "titles"; private static final int DATABASE_VERSION = 1; private static final String DATABASE_CREATE = "create table titles (_id integer primary key autoincrement, " + "isbn text not null, title text not null, " + "publisher text not null);"; private final Context context; private DatabaseHelper DBHelper; private SQLiteDatabase db; public DBAdapter(Context ctx) { this.context = ctx; DBHelper = new DatabaseHelper(context); } private static class DatabaseHelper extends SQLiteOpenHelper { DatabaseHelper(Context context) { super(context, DATABASE_NAME, null, DATABASE_VERSION); } @Override public void onCreate(SQLiteDatabase db) { db.execSQL(DATABASE_CREATE); } @Override public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) { Log.w(TAG, "Upgrading database from version " + oldVersion + " to " + newVersion + ", which will destroy all old data"); db.execSQL("DROP TABLE IF EXISTS titles"); onCreate(db); } } //---opens the database--- public DBAdapter open() throws SQLException { db = DBHelper.getWritableDatabase(); return this; } //---closes the database--- public void close() { DBHelper.close(); } //---insert a title into the database--- public long insertTitle(String isbn, String title, String publisher) { ContentValues initialValues = new ContentValues(); initialValues.put(KEY_ISBN, isbn); initialValues.put(KEY_TITLE, title); initialValues.put(KEY_PUBLISHER, publisher); return db.insert(DATABASE_TABLE, null, initialValues); } //---deletes a particular title--- public boolean deleteTitle(long rowId) { return db.delete(DATABASE_TABLE, KEY_ROWID + "=" + rowId, null) > 0; } //---retrieves all the titles--- public Cursor getAllTitles() { return db.query(DATABASE_TABLE, new String[] { KEY_ROWID, KEY_ISBN, KEY_TITLE, KEY_PUBLISHER}, null, null, null, null, null); } //---retrieves a particular title--- public Cursor getTitle(long rowId) throws SQLException { Cursor mCursor = db.query(true, DATABASE_TABLE, new String[] { KEY_ROWID, KEY_ISBN, KEY_TITLE, KEY_PUBLISHER }, KEY_ROWID + "=" + rowId, null, null, null, null, null); if (mCursor != null) { mCursor.moveToFirst(); } return mCursor; } //---updates a title--- public boolean updateTitle(long rowId, String isbn, String title, String publisher) { ContentValues args = new ContentValues(); args.put(KEY_ISBN, isbn); args.put(KEY_TITLE, title); args.put(KEY_PUBLISHER, publisher); return db.update(DATABASE_TABLE, args, KEY_ROWID + "=" + rowId, null) > 0; } } DatabaseActivity.java package com.example.database1; import android.os.Bundle; import android.app.Activity; import android.database.Cursor; import android.view.Menu; import android.widget.Toast; public class DatabaseActivity extends Activity { @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_database); DBAdapter db=new DBAdapter(this); db.open(); } } activity_database.xml: <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" xmlns:tools="http://schemas.android.com/tools" android:layout_width="match_parent" android:layout_height="match_parent"> <EditText android:id="@+id/edit1" android:layout_width="wrap_content" android:layout_height="wrap_content" /> <EditText android:id="@+id/edit2" android:layout_width="wrap_content" android:layout_height="wrap_content" /> <EditText android:id="@+id/edit3" android:layout_width="wrap_content" android:layout_height="wrap_content" /> <Button android:id="@+id/submit" android:layout_width="wrap_content" android:layout_height="wrap_content" /> </LinearLayout>

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  • Strange Exception on getGeneratedKeys() with JDBC for MySQL 5.1

    - by sweeney
    Hello, I'm using JDBC to insert a row into a MYSQL database. I build a parameterized command, execute it and attempt to retrieve the auto generated keys as follows: String sql = "INSERT IGNORE INTO `users` (`email`, `pass-hash`) VALUES (?, ?)"; Connection conn = SQLAccess.getConnection(); PreparedStatement ps = conn.prepareStatement(sql); ps.setString(1, login); ps.setString(2, passHash); int count = ps.executeUpdate(); if (count == 1) { ResultSet rs = ps.getGeneratedKeys(); rs.next(); //some more stuff... } For some reason, I get the following SQLException on the line containing ResultSet rs = ps.getGeneratedKeys();: !Statement.Generated Keys Not Requested! Any thoughts? When I run the same query, as generated by running the app through the debugger, in a MySQL browser it executes without incident. Thanks, brian

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  • PHP Prepared Statement Returns -1

    - by pws5068
    I've been using prepared statements for a little while now and I've never had any problems. Now I'm trying to: $sql="SELECT PhotoID,Caption FROM Photos WHERE EntityID=? AND TypeID=? LIMIT ?,?"; $iDB = new mysqliDB(); // Extends mysqli $stmt = $iDB->prepare($sql); $stmt->bind_param('iiii',$entityID,$typeID,$minRange,$maxRange); $stmt->execute(); $stmt->bind_result($photoID,$caption); echo("Affected={$stmt->affected_rows}"); This prints -1. I have triple tested that all 4 values in bindParam are set, and that the sql query works when pasted into myAdmin with the respective values. Any idea what may be causing this?

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  • Why would you want a case sensitive database?

    - by Khorkrak
    What are some reasons for choosing a case sensitive collation over a case insensitive one? I can see perhaps a modest performance gain for the DB engine in doing string comparisons. Is that it? If your data is set to all lower or uppercase then case sensitive could be reasonable but it's a disaster if you store mixed case data and then try to query it. You have then apply a lower() function on the column so that it'll match the corresponding lower case string literal. This prevents index usage in every dbms. So wondering why anyone would use such an option.

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  • Search over multiple fields

    - by schneck
    Hi there, I think I don't unterstand django-haystack properly: I have a data model containing several fields, and I would to have two of them searched: class UserProfile(models.Model): user = models.ForeignKey(User, unique=True, default=None) twitter_account = models.CharField(max_length=50, blank=False) My search index settings: class UserProfileIndex(SearchIndex): text = CharField(document=True, model_attr='user') twitter_account = CharField(model_attr='twitter_account') def get_queryset(self): """Used when the entire index for model is updated.""" return UserProfile.objects.all() But when I perform a search, only the field "username" is searched; "twitter_account" is ignored. When I select the Searchresults via dbshell, the objects contain the correct values for "user" and "twitter_account", but the result page shows a "no results": {% if query %} <h3>Results</h3> {% for result in page.object_list %} <p> <a href="{{ result.object.get_absolute_url }}">{{ result.object.id }}</a> </p> {% empty %} <p>No results</p> {% endfor %} {% endif %} Any ideas?

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