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  • Jquery UI accordion question - how would you approach this?

    - by E.J. Brennan
    I am using jquery UI accordion control in one of my apps asp.net apps. The data for the accordion comes from a database, and each database record has an ID, a Title Field and a content field. The title is the heading, and the content is the data that shows up when the draw is opened... I'd like to be able to call my page like this: http://www.mywebsite.com/mypage.aspx?ID=123 and have it display all the data (as it does now), but then have the default 'drawer' of the accordion open to the section that corresponds to the ID number passed in on the url...there are about 50 sections on the page. Any suggestions on how to approach this? My questions is specific to the jquery accordion function, the rest I know. So where would be the best place to 'tag' the drawer with the unique ID's, and then what is the snippet of javascript code (I assume) that I would use 'open' that drawer based on the ID passed in?? Thanks!

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  • Deselecting a form input and waiting for a function before submitting

    - by blcArmadillo
    I have a form with an input field where a user enters a unique identifier. I then have some jQuery code that upon the user moving away from the input field (blur) goes out and fetches details about the part and populates some fields on the page. The problem is if the user clicks the submit button before moving out of the input field the jQuery code never has a chance to load in the data and populate the necessary fields. Whats the best way to go about doing this? I thought about maybe setting the focus to body and then having an infinite loop that keeps checking the page until all fields that should be filled in have been filled in but I feel like some sort of event based solution would be better than unpredictable infinite loops. Any ideas?

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  • Transactional isolation level needed for safely incrementing ids

    - by Knut Arne Vedaa
    I'm writing a small piece of software that is to insert records into a database used by a commercial application. The unique primary keys (ids) in the relevant table(s) are sequential, but does not seem to be set to "auto increment". Thus, I assume, I will have to find the largest id, increment it and use that value for the record I'm inserting. In pseudo-code for brevity: id = select max(id) from some_table id++ insert into some_table values(id, othervalues...) Now, if another thread started the same transaction before the first one finished its insert, you would get two identical ids and a failure when trying to insert the last one. You could check for that failure and retry, but a simpler solution might be setting an isolation level on the transaction. For this, would I need SERIALIZABLE or a lower level? Additionally, is this, generally, a sound way of solving the problem? Are the any other ways of doing it?

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  • Mysql stored procedures

    - by Richard M
    Hello, I have a unique issue that I need advice on. I've been writing asp.net apps with SQL Server back ends for the past 10 years. During that time, I have also written some PHP apps, but not many. I'm going to be porting some of my asp.net apps to PHP and have run into a bit of an issue. In the Asp.net world, it's generally understood that when accessing any databases, using views or stored procedures is the preferred way of doing so. I've been reading some PHP/MySQL books and I'm beginning to get the impression that utilizing stored procedures in mysql is not advisable. I hesitate in using that word, advisable, but that's just the felling I get. So, the advice I'm looking for is basically, am I right or wrong? Do PHP developers use stored procedures at all? Or, is it something that is shunned? Thanks in advance.

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  • How do I find hash value of a 3D vector ?

    - by brainydexter
    I am trying to perform broad-phase collision detection with a fixed-grid size approach. Thus, for each entity's position: (x,y,z) (each of type float), I need to find which cell does the entity lie in. I then intend to store all the cells in a hash-table and then iterate through to report (if any) collisions. So, here is what I am doing: Grid-cell's position: (int type) (Gx, Gy, Gz) = (x / M, y / M, z / M) where M is the size of the grid. Once, I have a cell, I'd like to add it to a hash-table with its key being a unique hash based on (Gx, Gy, Gz) and the value being the cell itself. Now, I cannot think of a good hash function and I need some help with that. Can someone please suggest me a good hash function? Thanks

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  • mongoid with rails - Database should be a Mongo::DB, not NilClass"

    - by Adam T
    Greetings I am trying to get Mongoid to work with my Rails app and I am getting an error: "Mongoid::Errors::InvalidDatabase in 'Shipment bol should be unique' Database should be a Mongo::DB, not NilClass" I have created the mongoid.yml file in my config directory and have mongodb running as a daemon. The config file is like so: defaults: &defaults host: localhost development: <<: *defaults database: ship-it-development test: <<: *defaults database: ship-it-test production: <<: *defaults host: <%= ENV['MONGOID_HOST'] % port: <%= ENV['MONGOID_PORT'] % database: <%= ENV['MONGOID_DATABASE'] % All of my specs fail with the above error. I am using rails 2.3.8. Anyone have ideas?

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  • alignment and granularity of mmap

    - by OwnWaterloo
    I am confused by the specification of mmap. Let pa be the return address of mmap (the same as the specification) pa = mmap(addr, len, prot, flags, fildes, off); In my opinion after the function call succeed the following range is valid [ pa, pa+len ) My question is whether the range of the following is still valid? [ round_down(pa, pagesize) , round_up(pa+len, pagesize) ) [ base, base + size ] for short That is to say: is the base always aligned on the page boundary? is the size always a multiple of pagesize (the granularity is pagesize in other words) Thanks for your help. I think it is implied in this paragraph : The off argument is constrained to be aligned and sized according to the value returned by sysconf() when passed _SC_PAGESIZE or _SC_PAGE_SIZE. When MAP_FIXED is specified, the application shall ensure that the argument addr also meets these constraints. The implementation performs mapping operations over whole pages. Thus, while the argument len need not meet a size or alignment constraint, the implementation shall include, in any mapping operation, any partial page specified by the range [pa,pa+len). But I'm not sure and I do not have much experience on POSIX. Please show me some more explicit and more definitive evidence Or show me at least one system which supports POSIX and has different behavior Thanks agian.

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  • What are people's opinions vis-a-vis my choice of authorization plugins?

    - by brad
    I'm slowly but surely putting together my first rails app (first web-app of any kind in fact - I'm not really a programmer) and it's time to set up a user registration/login system. The nature of my app is such that each user will be completely separated from each other user (except for admin roles). When users log in they will have their own unique index page looking at only their data which they and no-one else can ever see or edit. However, I may later want to add a role for a user to be able to view and edit several other user's data (e.g. a group of users may want to allow their secretary to access and edit their data but their secretary would not need any data of their own). My plan is to use authlogic to create the login system and declarative authorization to control permissions but before I embark on this fairly major and crucial task I thought I would canvas a few opinions as to whether this combo was appropriate for the tasks I envisage or whether there would be a better/simpler/faster/cheaper/awesomer option.

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  • How to enforce foreign keys using Xerial SQLite JDBC?

    - by Space_C0wb0y
    According to their release notes, the Xerial SQLite JDBC driver supports foreign keys since version 3.6.20.1. I have tried some time now to get a foreign key constraint to be enforced, but to no avail. Here is what I came up with: public static void main(String[] args) throws ClassNotFoundException, SQLException { Class.forName("org.sqlite.JDBC"); SQLiteConfig config = new SQLiteConfig(); config.enforceForeignKeys(true); Connection connection = DriverManager.getConnection("jdbc:sqlite::memory:", config.toProperties()); connection.createStatement().executeUpdate( "CREATE TABLE artist(" + "artistid INTEGER PRIMARY KEY, " + "artistname TEXT);"); connection.createStatement().executeUpdate( "CREATE TABLE track("+ "trackid INTEGER," + "trackname TEXT," + "trackartist INTEGER," + "FOREIGN KEY(trackartist) REFERENCES artist(artistid)" + ");"); connection.createStatement().executeUpdate( "INSERT INTO track VALUES(14, 'Mr. Bojangles', 3)"); } The table definitions are taken directly from the sample in the SQLite documentation. This is supposed to fail, but it doesn't. I also checked, and it really inserts the tuple (no ignore or something like that). Does anyone have any experience with that, or knows how to make it work?

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  • SCD2 + Merge Statement + SQL Server

    - by Nev_Rahd
    I am trying work out with MERGE statment to Insert / Update Dimension Table of Type SCD2 My source is a Table var to Merge with Dimension table. My MERGE statement is throwing an error as: The target table 'DM.DATA_ERROR.ERROR_DIMENSION' of the INSERT statement cannot be on either side of a (primary key, foreign key) relationship when the FROM clause contains a nested INSERT, UPDATE, DELETE, or MERGE statement. Found reference constraint 'FK_ERROR_DIMENSION_to_AUDIT_CreatedBy'. My MERGE Statement: DECLARE @DATAERROROBJECT AS [ERROR_DIMENSION] INSERT INTO DM.DATA_ERROR.ERROR_DIMENSION SELECT ERROR_CODE, DATA_STREAM_ID, [ERROR_SEVERITY], DATA_QUALITY_RATING, ERROR_LONG_DESCRIPTION, ERROR_DESCRIPTION, VALIDATION_RULE, ERROR_TYPE, ERROR_CLASS, VALID_FROM, VALID_TO, CURR_FLAG, CREATED_BY_AUDIT_SK, UPDATED_BY_AUDIT_SK FROM (MERGE DM.DATA_ERROR.ERROR_DIMENSION ED USING @DATAERROROBJECT OBJ ON(ED.ERROR_CODE = OBJ.ERROR_CODE AND ED.DATA_STREAM_ID = OBJ.DATA_STREAM_ID) WHEN NOT MATCHED THEN INSERT VALUES( OBJ.ERROR_CODE ,OBJ.DATA_STREAM_ID ,OBJ.[ERROR_SEVERITY] ,OBJ.DATA_QUALITY_RATING ,OBJ.ERROR_LONG_DESCRIPTION ,OBJ.ERROR_DESCRIPTION ,OBJ.VALIDATION_RULE ,OBJ.ERROR_TYPE ,OBJ.ERROR_CLASS ,GETDATE() ,'9999-12-13' ,'Y' ,1 ,1 ) WHEN MATCHED AND ED.CURR_FLAG = 'Y' AND ( ED.[ERROR_SEVERITY] <> OBJ.[ERROR_SEVERITY] OR ED.[DATA_QUALITY_RATING] <> OBJ.[DATA_QUALITY_RATING] OR ED.[ERROR_LONG_DESCRIPTION] <> OBJ.[ERROR_LONG_DESCRIPTION] OR ED.[ERROR_DESCRIPTION] <> OBJ.[ERROR_DESCRIPTION] OR ED.[VALIDATION_RULE] <> OBJ.[VALIDATION_RULE] OR ED.[ERROR_TYPE] <> OBJ.[ERROR_TYPE] OR ED.[ERROR_CLASS] <> OBJ.[ERROR_CLASS] ) THEN UPDATE SET ED.CURR_FLAG = 'N', ED.VALID_TO = GETDATE() OUTPUT $ACTION ACTION_OUT, OBJ.ERROR_CODE ERROR_CODE, OBJ.DATA_STREAM_ID DATA_STREAM_ID, OBJ.[ERROR_SEVERITY] [ERROR_SEVERITY], OBJ.DATA_QUALITY_RATING DATA_QUALITY_RATING, OBJ.ERROR_LONG_DESCRIPTION ERROR_LONG_DESCRIPTION, OBJ.ERROR_DESCRIPTION ERROR_DESCRIPTION, OBJ.VALIDATION_RULE VALIDATION_RULE, OBJ.ERROR_TYPE ERROR_TYPE, OBJ.ERROR_CLASS ERROR_CLASS, GETDATE() VALID_FROM, '9999-12-31' VALID_TO, 'Y' CURR_FLAG, 555 CREATED_BY_AUDIT_SK, 555 UPDATED_BY_AUDIT_SK ) AS MERGE_OUT WHERE MERGE_OUT.ACTION_OUT = 'UPDATE'; What am I doing wrong ?

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  • How Do I Convert text to a WAV file With Inaudible Waveform?

    - by Scott
    I am trying to create an audio watermarking system. I figure the best solution is to create an audio file (WAV) based on a unique string of text and then combine this with the original wav. The part that makes this tricky (for me anyway) is: How do I convert the text string to a wav? How do I ensure that the resulting WAV form is inaudible (or at least barely noticeable to the listener). I would prefer this be done server side (via PHP, etc) but if the processing load isn't too much then would be ok with something in Flash or Javascript. I'd be willing to pay someone to create me a workable solution (complete source code that functions as described). Thanks, Scott!

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  • SQLite multi process access

    - by Nicolas
    Hello, We are using SQLite in a multi processes and multi threaded application. The SQLite database files are encrypted using the embedded SQLite encryption. The FAQ states that SQLite should be able to manage multi process accesses using locks mechanism. We are experiencing a strange problem: When many threads are accessing the same database file, sometime constrains violations occur, more specifically - a field with a unique constrain is getting duplicate values after calling "insert or replace" statement. It happens quite often now, that we are using the encryption. Before we started using SQLite encryption we did not notice such a behavior. Are there any specific known issues with this?

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  • polymorphic hql

    - by Berryl
    I have a base type where "business id" must be unique for a given subclass, but it is possible for there to be different subclasses with the same business id. If there is a base type with a requested id but of the wrong subclass I want to return null, using a named query. The code below does this, but I am wondering if I can avoid the try/catch with a better HQL. Can I? Cheers, Berryl current hql <query name="FindActivitySubjectByBusinessId"> <![CDATA[ from ActivitySubject act where act.BusinessId = :businessId ]]> </query> current fetch code public ActivitySubject FindByBusinessId<T>(string businessId) where T : ActivitySubject { Check.RequireStringValue(businessId, "businessId"); try { return _session.GetNamedQuery("FindActivitySubjectByBusinessId") .SetString("businessId", businessId) .UniqueResult<T>(); } catch (InvalidCastException e) { // an Activity Subject was found with the requested id but the wrong type return null; } }

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  • Entity Relationship Multiple 1:1's

    - by Evan
    I have an application where I have a generic object (table) called Hull. Each hull in the table is unique. I have another object that has three hulls, but they are specifically the Port_Hull, Center_Hull and Starboard_Hull. Rather than create a One to Many relationship, I was trying to create a one to one relationship for each one, but this results in numerous errors unless I make the relationship from Hull to Vessel one to many (which it is not). Any idea how I go about this, or should I abandon the concept and make the vessel to hull relationship one to many and deal with lists that always have three entries? p.s. Using uniqueidentifiers as many users can be adding records while disconnected. Hull Table HullID uniqueidentifier (primary key) plus bunch of hull data fields Vessel Table VesselID uniqueidentifier (primary key) MainHullID uniqueidentifier (tried as key and non-key) PortHullID uniqueidentifier StarboardHullID uniqueidentifier plus bunch of Vessel data fields

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  • Grails XOM linkageerror - SAXParserException

    - by Stefan Kendall
    Possibly related: http://stackoverflow.com/questions/2762439/grails-attempting-to-include-htppbuilder-linkage-error I'm trying to include XOM in my grails project. How do I know which dependency library I need to exclude? I'm lost here. dependencies { build('xom:xom:1.1') { excludes "xml-apis" } } Error: java.lang.LinkageError: loader constraint violation: loader (instance of <bootloader>) previously initiated loading for a different type with name "org/xml/sax/SAXParseException" at java.lang.Class.getDeclaredMethods0(Native Method) at java.lang.Class.privateGetDeclaredMethods(Class.java:2427) at java.lang.Class.getDeclaredMethods(Class.java:1791) at java.security.AccessController.doPrivileged(Native Method) at org.codehaus.groovy.util.LazyReference.getLocked(LazyReference.java:33) at org.codehaus.groovy.util.LazyReference.get(LazyReference.java:20) at grails.util.PluginBuildSettings.getPluginInfos(PluginBuildSettings.groovy:124) at grails.util.PluginBuildSettings.getPluginInfos(PluginBuildSettings.groovy) at grails.util.PluginBuildSettings$getPluginInfos.callCurrent(Unknown Source) at grails.util.PluginBuildSettings.getPluginInfo(PluginBuildSettings.groovy:160) at grails.util.PluginBuildSettings$getPluginInfo.callCurrent(Unknown Source) at grails.util.PluginBuildSettings.getPluginInfoForSource(PluginBuildSettings.groovy:195) at org.codehaus.groovy.transform.ASTTransformationVisitor$3.call(ASTTransformationVisitor.java:303) at org.codehaus.groovy.control.CompilationUnit.applyToSourceUnits(CompilationUnit.java:820) at org.codehaus.groovy.control.CompilationUnit.doPhaseOperation(CompilationUnit.java:513) at org.codehaus.groovy.control.CompilationUnit.processPhaseOperations(CompilationUnit.java:489) at org.codehaus.groovy.control.CompilationUnit.compile(CompilationUnit.java:466) at _GrailsEvents_groovy.run(_GrailsEvents_groovy:54) at _GrailsEvents_groovy$run.call(Unknown Source) at _GrailsArgParsing_groovy$run.call(Unknown Source) at _GrailsArgParsing_groovy.run(_GrailsArgParsing_groovy:29) at _GrailsArgParsing_groovy$run.call(Unknown Source) at _GrailsInit_groovy$run.call(Unknown Source) at _GrailsInit_groovy.run(_GrailsInit_groovy:38) at _GrailsInit_groovy$run.call(Unknown Source) at Help_.run(Help_.groovy:27) at Help_$run.call(Unknown Source) at gant.Gant.processTargets(Gant.groovy:494) at gant.Gant.processTargets(Gant.groovy:480)

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  • which collection should I use

    - by Masna
    Hello, I have a number of custom objects of type X. X has a number of parameters and must be unique in the collection. (I created my own equals method based on the custom parameters to examine this) In each object of type x, I have a list of objects y. I want to add/remove/modify easily an object y. For example: To write the add method, it would be something like add(objTypeX, objTypeY) I would check or the collections already has a objTypeX. If so: i would add the objTypeY to the already existing objTypeX else: i would create objTypeX and add objTypeY to this object. To modify an objTypeY, it would be something like(objTypeX, objTypeY, newobjTypeY) I would get objTypeX out of the collections and modify objTypeY to newobjTypeY Which collections should I use? I tried with hashset but i can get a specific object out of the list, without run down the list till I find that object. I develop this in vb.net 3.5

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  • Zip up web page groups to view in browsers

    - by Arlen Beiler
    There should be a standard for saving viewing bunches of webpages as a website. For instance, say I have a whole bunch of pages, such as I get from the WordPress plugin "Really Static" which saves an entire site, and I have all the links start with a slash. Now, I can't really use those links if I am reading it from the file system. If there would be a standard where we could zip up files, give them a unique extension (like "hzip" for html zip), and open the file with any browser, which would display it as though the root of that file were the root of the pages. "http://example.com" The links would all work right. This would facilitate sharing and copying groups of webpages.

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  • C++: A variation of priority queue

    - by Helltone
    I need some kind of priority queue to store pairs <key, value>. Values are unique, but keys aren't. I will be performing the following operations (most common first): random insertion; retrieving (and removing) all elements with the least key. random removal (by value); I can't use std::priority_queue because it only supports removing the head. For now, I'm using an unsorted std::list. Insertion is performed by just pushing new elements to the back (O(1)). Operation 2 sorts the list with std::sort (O(N*logN)), before performing the actual retrieval. Removal, however, is O(n), which is a bit expensive. Any idea of a better data structure?

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  • Google Local Search API

    - by Gublooo
    hey guys couple of quick questions 1) In the local search results - we can get a lot of parameters like street title, address, city, state, lat, long , url etc - In order for me to uniquely identify this record - can I consider URL to be unique to this address or concatenation of latitude and longitude Ref: http://code.google.com/apis/ajaxsearch/documentation/reference.html#_class_GlocalResult 2) In terms of usage, depending upon what user enters, I'm displaying a list of local business for the user to choose. Now when a user selects a particular business address - is it legal for me to store that business address along with lat and longitude information in my database for future look ups. I've seen a lot of blogs talking about storing the lat/long info but just want to be sure that i'm not violating and google rules. Thanks

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  • ASP.NET 4.5 Bundling in Debug Mode - Stale Resources

    - by RPM1984
    Is there any way we can make the ASP.NET 4.5 Bundling functionality generate GUID's as part of the querystring when running in debug mode (e.g bundling turned OFF). The problem is when developing locally, the scripts/CSS files are generated like this: <script type="text/javascript" src="/Content/Scripts/myscript.js" /> So if i change that file, i need to do a hard-refresh (sometimes a few times) to get the file to be picked up by the browser - annoying. Is there any way we can make it render out like this: <script type="text/javascript" src="/Content/Scripts/myscript.js?v=x" /> Where x is a GUID (e.g always unique). Ideas? I'm on ASP.NET MVC 4.

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  • Dynamic Selectors with Jquery with php while loop

    - by Anders Kitson
    I have a while loop which creates a list of anchor tags each with a unique class name counting from 1 to however many items there are. I would like to change a css attriubute on a specific anchor tag and class when it is clicked so lets say the background color is changed. Here is my code while($row = mysql_fetch_array($results)){ $title = $row['title']; $i++; echo "<a class='$i'>$title</a> } I would like my jquery to look something like this, it is obviously going to be more complicated than this I am just confused as where to start. $(document).ready(function() { $('a .1 .2 .3 .4 and so on').click(function() { $('a ./*whichever class was clicked*/').css('background':'red'); }); });

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  • HowTo init Django model, before using it?

    - by mosg
    Hi. I'm new to python and django. Apps | Versions: Python 2.6.2 Django (working with PostgreSQL) Question: I wrote a simple model: class OperationType(models.Model): eid = models.IntegerField(unique=True) name = models.CharField(max_length=64) def __unicode__(self): tpl = 'eid="', str(self.eid), '" name="', self.name, '"' return ''.join(tpl) Now I need to initialize it, for example with this data: 0, "None" 1, "Add" 2, "Edit" 3, "Delete" But I need to initialize this data not with admin web panel, but after class model created in the same code. How to do this? Thanks for help!

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  • Windows Mobile : How to bind dropdown's selectedvalue to a column in table A and the list data to a

    - by Rob
    Hi, I am trying to learn the basics of Windows Mobile development against SQL CE and have come across a basic problem. I have two tables. One called Customers that stores customer info and has an identity column called ID as the primary key. The other table is called Orders which has a column called CustomerID (the FK constraint is present). I have added a DataSet to the project that contains both tables and have autogenerated the edit/view forms. This has produced a text control for the CustomerID column in the Order table for the new/edit form and I deleted it and replaced it with a dropdown list. Then, using the 'Advanced' databinding options (in Properties) I set the datasource of the list to the Customers table setting the value to the ID field and the text to the CustomerName field. I then set the SelectedValue of the list box to the CustomerID field of the Orders dataset. So far so good. When I run the app in the emulator and view the 'New' form for Orders the Customer dropdown is indeed populated with a list of customer names and I can select one and happily create a new order successfully. This is confirmed when I see the order appear in the Orders Grid form. However, when I then click on the order in the grid and then select 'Edit' the order loads but the dropdown always shows the first customer in the list and doesn't seem to bind the SelectedValue to the Orders dataset CustomerID field. Now I am an ASP.NET guy and normally hand craft the DAL and it's binding to the UI so I'm not entirely sure where to look to investigate what is going wrong here as this is all generated code. I am sure it is something very trivial but any pointers would be appreciated. My gut feeling is that the SelectedValue and the Customers.CustomerID values do not match for some reason? Many thanks, Rob.

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  • keep duplicate number records only - perl

    - by manu
    Hello I have one text string which is having some duplicate characters (FFGGHHJKL), these can be made unique by using the positive lookahead [perl script for the same$ perl -pe 's/(.)(?=.*?\1)//g']. (FFEEDDCCGG OUTPUT == FEDCG) My question is how to make it work on the numbers (Ex. 212 212 43 43 5689 6689 5689 71 81 === output should be 212 43 5689 6689 71 81) ? Also if we want to have only duplicate records to be given as the output from a file having n rows (212 212 43 43 5689 6689 5689 71 81 \n 66 66 67 68 69 69 69 71 71 52 ..\n .. .. \n... OUTPUT == 212 212 43 43 5689 5689 \n 66 66 69 69 69 71 71) then what should be done ? Thanks and regards -manu

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  • Creating self-referential tables with polymorphism in SQLALchemy

    - by Jace
    I'm trying to create a db structure in which I have many types of content entities, of which one, a Comment, can be attached to any other. Consider the following: from datetime import datetime from sqlalchemy import create_engine from sqlalchemy import Column, ForeignKey from sqlalchemy import Unicode, Integer, DateTime from sqlalchemy.orm import relation, backref from sqlalchemy.ext.declarative import declarative_base Base = declarative_base() class Entity(Base): __tablename__ = 'entities' id = Column(Integer, primary_key=True) created_at = Column(DateTime, default=datetime.utcnow, nullable=False) edited_at = Column(DateTime, default=datetime.utcnow, onupdate=datetime.utcnow, nullable=False) type = Column(Unicode(20), nullable=False) __mapper_args__ = {'polymorphic_on': type} # <...insert some models based on Entity...> class Comment(Entity): __tablename__ = 'comments' __mapper_args__ = {'polymorphic_identity': u'comment'} id = Column(None, ForeignKey('entities.id'), primary_key=True) _idref = relation(Entity, foreign_keys=id, primaryjoin=id == Entity.id) attached_to_id = Column(Integer, ForeignKey('entities.id'), nullable=False) #attached_to = relation(Entity, remote_side=[Entity.id]) attached_to = relation(Entity, foreign_keys=attached_to_id, primaryjoin=attached_to_id == Entity.id, backref=backref('comments', cascade="all, delete-orphan")) text = Column(Unicode(255), nullable=False) engine = create_engine('sqlite://', echo=True) Base.metadata.bind = engine Base.metadata.create_all(engine) This seems about right, except SQLAlchemy doesn't like having two foreign keys pointing to the same parent. It says ArgumentError: Can't determine join between 'entities' and 'comments'; tables have more than one foreign key constraint relationship between them. Please specify the 'onclause' of this join explicitly. How do I specify onclause?

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