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  • SQLAlchemy: a better way for update with declarative?

    - by hadrien
    I am a SQLAlchemy noob. Let's say I have an user table in declarative mode: class User(Base): __tablename__ = 'user' id = Column(u'id', Integer(), primary_key=True) name = Column(u'name', String(50)) When I know user's id without object loaded into session, I update such user like this: ex = update(User.__table__).where(User.id==123).values(name=u"Bob Marley") Session.execute(ex) I dislike using User.__table__, should I stop worrying with that? Is there a better way to do this? Thanx!

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  • mysql foreign key problem.

    - by JP19
    Hi, What is wrong with the foreign key addition here: mysql> create table notes ( id int (11) NOT NULL auto_increment PRIMARY KEY, note_type_id smallint(5) NOT NULL, data TEXT NOT NULL, created_date datetime NOT NULL, modified_date timestamp NOT NULL on update now()) Engine=InnoDB; Query OK, 0 rows affected (0.08 sec) mysql> create table notetypes ( id smallint (5) NOT NULL auto_increment PRIMARY KEY, type varchar(255) NOT NULL UNIQUE) Engine=InnoDB; Query OK, 0 rows affected (0.00 sec) mysql> alter table `notes` add constraint foreign key(`note_type_id`) references `notetypes`.`id` on update cascade on delete restrict; ERROR 1005 (HY000): Can't create table './admin/#sql-43e_b762.frm' (errno: 150) Thanks JP

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  • Composite keys as Foreign Key?

    - by paulio
    I have the following table... TABLE: Accounts ID (int, PK, Identity) AccountType (int, PK) Username (varchar) Password (varchar) I have created a composite key out of ID and AccountType columns so that people can have the same username/password but different AccountTypes. Does this mean that for each foreign table that I try and link to I'll have to create two columns? I’m using SQL Server 2008

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  • How do you create a transaction that spans multiple statements in Python with MySQLdb?

    - by Fast Fish
    I know that with an InnoDB table, transactions are autocommit, however I understand that to mean for a single statement? For example, I want to check if a user exists in a table, and then if it doesn't, create it. However there lies a race condition. I believe using a transaction prior to doing the select, will ensure that the table remains untouched until the subsequent insert, and the transaction is committed. How can you do this with MySQLdb and Python?

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  • Retrieving information from DOM elements returned using ajax

    - by niczoom
    I am new(ish) to jQuery and am testing out the extraction of DOM element data using jQuery. Below, detailed on the firebug console I tried to extract data 10 different ways (from 1- to 10-) using data returned directly from the ajax request (rtnData). And then to compare, I wrapped (rtnData) in a div to make it a jQuery object, and stored it in $test, (var $test= $('<div/>').html(rtnData);) Displayed below in Firebug Console Output, I cant figure out is why 5- return's nothing and e- returns the center tag contents. Same with 8- and e-, they both look for #ticker div id but 8- returns nothing and e- returns the correct html?? Also when searching for h1 tag .text(), why does 10- return blank and j- return the correct data? Thanks, Nic. Use the following page to run the ajax request below in Firebug Console: http://www.liamharding.com/pgi/pgi.php jQuery code ran using Firebug Console: $.ajax({ url: 'pgiproxy.php', type: 'POST', dataType: 'html', data: ({ data : $("#formdata").serialize(), mode : "graph"}), success: function(rtnData){ console.log("0- ", rtnData); console.log("1- ", $('img', rtnData)); console.log("2- ", $('a', rtnData)); console.log("3- ", $('span.cr', rtnData)); console.log("4- ", $('span.cr', rtnData).html()); console.log("5- ", $('center', rtnData)); console.log("6- ", $('table', rtnData)); console.log("7- ", $('#ticker_data', rtnData)); console.log("8- ", $('#ticker', rtnData)); console.log("9- ", $('#last', rtnData)); console.log("10- ", $('h1', rtnData).text()); var $test= $('<div/>').html(rtnData); console.log("z- ", $test); console.log("a- ", $('img', $test)); console.log("b- ", $('a', $test)); console.log("c- ", $('span.cr', $test)); console.log("d- ", $('span.cr', $test).html()); console.log("e- ", $('center', $test)); console.log("f- ", $('table', $test)); console.log("g- ", $('#ticker_data', $test)); console.log("h- ", $('#ticker', $test)); console.log("i- ", $('#last', $test)); console.log("j- ", $('h1', $test).text()); }, error: function(){ alert('ERROR'); } }); Firebug Console Output: 1- jQuery(img#GnuPlotChart 624e4629...8946.gif) 2- jQuery(a.button javascri...eload();, a.button javascri...close();) 3- jQuery(span.cr) 4- <span class="tl"></span><span class="tr"></span><span class="bl"></span><span class="br"></span> 5- jQuery() 6- jQuery(table.rbox-table) 7- jQuery(div#ticker_data.rbox) 8- jQuery() 9- jQuery(th#last, td#last.num) 10- z- jQuery(div) a- jQuery(img#GnuPlotChart 624e4629...8946.gif) b- jQuery(a.button javascri...eload();, a.button javascri...close();) c- jQuery(span.cr) d- <span class="tl"></span><span class="tr"></span><span class="bl"></span><span class="br"></span> e- jQuery(center) f- jQuery(table.rbox-table, table) g- jQuery(div#ticker_data.rbox) h- jQuery(div#ticker) i- jQuery(th#last, td#last.num) j- Legacy Charts

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  • Joining a one-to-many association with a many-to-many association in Rails 3

    - by Maz
    Hi all, I have a many-to-many association between a User class and a Table class. Additionally, i have a one-to-many association between the User and the Table (one User ultimately owns the table). I am trying to access all of the tables which the user may access (essintally joining both associations). Additionally, it would be nice to do this this with named_scope (now scope) Here's what I have so far: class User < ActiveRecord::Base acts_as_authentic attr_accessible :email, :password, :password_confirmation has_many :feedbacks has_many :tables has_many :user_table_permissions has_many :editableTables, :class_name => "Table", :through => :user_table_permissions def allTables editableTables.merge(tables) end end Thanks.

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  • Reverse Expression.Like criterion

    - by Joel Potter
    How should I go about writing a backwards like statement using NHibernate criteria? WHERE 'somestring' LIKE [Property] + '%' Sub Question: Can you access the abstract root alias in a SQLCriterion expression? This is somewhat achievable using the SQLCriterion expression Expression.Sql("? like {alias}.[Property] + '.%'", value, NHibernateUtil.String); However, in the case of class inheritance, {alias} is replaced with the incorrect alias for the column. Example (these classes are stored in separate tables): public abstract class Parent { public virtual string Property { get; set; } } public class Child : Parent { } The above query executed with Child as the root type will replace {alias} with the alias to the Child table rather than the Parent table. This results in an invalid column exception. I need to execute a like statement as above where the property exists on the parent table rather than on the root type table.

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  • Azure batch operations delete several blobs and tables

    - by reft
    I have a function that deletes every table & blob that belongs to the affected user. CloudTable uploadTable = CloudStorageServices.GetCloudUploadsTable(); TableQuery<UploadEntity> uploadQuery = uploadTable.CreateQuery<UploadEntity>(); List<UploadEntity> uploadEntity = (from e in uploadTable.ExecuteQuery(uploadQuery) where e.PartitionKey == "uploads" && e.UserName == User.Idendity.Name select e).ToList(); foreach (UploadEntity uploadTableItem in uploadEntity) { //Delete table TableOperation retrieveOperationUploads = TableOperation.Retrieve<UploadEntity>("uploads", uploadTableItem.RowKey); TableResult retrievedResultUploads = uploadTable.Execute(retrieveOperationUploads); UploadEntity deleteEntityUploads = (UploadEntity)retrievedResultUploads.Result; TableOperation deleteOperationUploads = TableOperation.Delete(deleteEntityUploads); uploadTable.Execute(deleteOperationUploads); //Delete blob CloudBlobContainer blobContainer = CloudStorageServices.GetCloudBlobsContainer(); CloudBlockBlob blob = blobContainer.GetBlockBlobReference(uploadTableItem.BlobName); blob.Delete(); } Each table got its own blob, so if the list contains 3 uploadentities, the 3 table and the 3 blobs will be deleted. I heard you can use table batch operations for reduce cost and load. I tried it, but failed miserable. Anyone intrested in helping me:)? Im guessing tablebatch operations are for tables only, so its a no go for blobs, right? How would you add tablebatchoperations for this code? Do you see any other improvements that can be done? Thanks!

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  • How to make Entity Key Mapping in Entity Framework like sql's foreign key?

    - by programmerist
    I try to give entity map on my entity app. But how can I do it? I try to make it like below: var test = ( from k in Kartlar where k.Rehber..... above codes k.(can not see Rehber or not working ) if you are correct , i can write k.Rehber.ID and others. i can not write: from k in Kartlar where k.Rehber.ID = 123 //assuming that navigation property name is Rehbar and its primary key of Rehbar table is ID && k.Kampanya.ID = 345 //assuming that navigation property name is Kampanya and its primary //key of Kampanya table is ID && k.Birim.ID = 567 //assuming that navigation property name is Birim and its primary key of Birim table is ID select k images you can see: also: You should look : http://i42.tinypic.com/2nqyyc6.png I have a table it includes 3 foreign key field like that: My Table: Kartlar ID (Pkey) RehberID (Fkey) KampanyaID (Fkey) BrimID (Fkey) Name Detail How can i write entity query with LINQ ? select * from Kartlar where RehberID=123 and KampanyaID=345 and BrimID=567 BUT please be careful I can not see RehberID, KampanyaID, BrimID in entity they are foreign key. I should use entity key but how?

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  • Make a usable Join relationship with LINQ on top of a database CSV design error

    - by jdk
    I'm looking for a way to fix and/or abstract away a comma-separated values (CSV) list in a database field in order to reconstruct a usable relationship such that I can properly join the two tables below and query them using LINQ and its Join method. Following is a sample showing the Person table and CsvArticleIds field having a CSV value to represent a one-to-many association with Article records. TABLE [dbo].[Person] Id Name CsvArticleIds -- ---------- -------- 1 Joe "15,22" 5 Ed "22" 10 Arnie "8,15,22" ^^^(Of course a link table should have been created; nonetheless the relationship with articles is trapped inside that list of CSV values.) TABLE [dbo].[Article] Id Title -- ---------- 8 Beginning C# 15 A Historic look at Programming in the 90s 22 Gardening in January Additional Info the fix can be at any level: C#.NET or SQL Server something easy because I will be repeating the solution for many other CSV values in other tables. Elegant is nice too. not looking for efficiency because this is part of a one-time data migration task and can take as long as it wants to run.

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  • Removing "Using temporary; Using filesort" from this MySQL select+join+group by query

    - by claytontstanley
    I have the following query: select t.Chunk as LeftChunk, t.ChunkHash as LeftChunkHash, q.Chunk as RightChunk, q.ChunkHash as RightChunkHash, count(t.ChunkHash) as ChunkCount from chunksubset as t join chunksubset as q on t.ID = q.ID group by LeftChunkHash, RightChunkHash And the following explain table: id select_type table type possible_keys key key_len ref rows Extra 1 SIMPLE subsets ref PRIMARY,IDIndex,SubsetIndex SubsetIndex 767 const 522014 "Using where; Using temporary; Using filesort" 1 SIMPLE subsets eq_ref PRIMARY,IDIndex,SubsetIndex PRIMARY 771 sotero.subsets.Id,const 1 "Using where; Using index" 1 SIMPLE c ref IDIndex IDIndex 4 sotero.subsets.Id 12 "Using where" 1 SIMPLE c ref IDIndex IDIndex 4 sotero.subsets.Id 12 note the "using temporary; using filesort". When this query is run, I quickly run out of RAM (presumably b/c of the temp table), and then the HDD kicks in, and the query slows to a halt. I thought it might be an index issue, so I started adding a few that sort of made sense: Table Non_unique Key_name Seq_in_index Column_name Collation Cardinality Sub_part Packed Null Index_type Comment Index_comment chunks 0 PRIMARY 1 ChunkId A 17796190 NULL NULL BTREE chunks 1 ChunkHashIndex 1 ChunkHash A 243783 NULL NULL BTREE chunks 1 IDIndex 1 Id A 1483015 NULL NULL BTREE chunks 1 ChunkIndex 1 Chunk A 243783 NULL NULL BTREE chunks 1 ChunkTypeIndex 1 ChunkType A 2 NULL NULL BTREE chunks 1 chunkHashByChunkIDIndex 1 ChunkHash A 243783 NULL NULL BTREE chunks 1 chunkHashByChunkIDIndex 2 ChunkId A 17796190 NULL NULL BTREE chunks 1 chunkHashByChunkTypeIndex 1 ChunkHash A 243783 NULL NULL BTREE chunks 1 chunkHashByChunkTypeIndex 2 ChunkType A 261708 NULL NULL BTREE chunks 1 chunkHashByIDIndex 1 ChunkHash A 243783 NULL NULL BTREE chunks 1 chunkHashByIDIndex 2 Id A 17796190 NULL NULL BTREE But still using the temporary table. The db engine is MyISAM. How can I get rid of the using temporary; using filesort in this query? Just changing to InnoDB w/o explaining the underlying cause is not a particularly satisfying answer. Besides, if the solution is to just add the proper index, then that's much easier than migrating to another db engine.

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  • Saving auto increment in MySQL

    - by oshafran
    Hello, I am trying to sync between 2 tables: I have active table where has auto_increment, and I have archive table with the same values. I would like both ID's to be unique (between the tables as well) - I mean, I would like to save auto incremenet, and if I UNION both table I still have uniqness. How can I do that? Is there a possibility to save auto increment when mysql is off?

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  • PHP - Nested Looping Trouble

    - by Jeremy A
    I have an HTML table that I need to populate with the values grabbed from a select statement. The table cols are populated by an array (0,1,2,3). Each of the results from the query will contain a row 'GATE' with a value of (0-3), but there will not be any predictability to those results. One query could pull 4 rows with 'GATE' values of 0,1,2,3, the next query could pull two rows with values of 1 & 2, or 1 & 3. I need to be able to populate this HTML table with values that correspond. So HTML COL 0 would have the TTL_NET_SALES of the db row which also has the GATE value of 0. <?php $gate = array(0,1,2,3); $gate_n = count($gate); /* Database = my_table.ID my_table.TT_NET_SALES my_table.GATE my_table.LOCKED */ $locked = "SELECT * FROM my_table WHERE locked = true"; $locked_n = count($locked); /* EXAMPLE RETURN Row 1: my_table['ID'] = 1 my_table['TTL_NET_SALES'] = 1000 my_table['GATE'] = 1; Row 2: my_table['ID'] = 2 my_table['TTL_NET_SALES'] = 1500 my_table['GATE'] = 3; */ print "<table border='1'>"; print "<tr><td>0</td><td>1</td><td>2</td><td>3</td>"; print "<tr>"; for ($i=0; $i<$locked_n; $i++) { for ($g=0; $g<$gate_n; $g++) { if (!is_null($locked['TTL_NET_SALES'][$i]) && $locked['GATE'][$i] == $gate[$g]) { print "<td>$".$locked['TTL_NET_SALES'][$i]."</td>"; } else { print "<td>-</td>"; } } } print "</tr>"; print "</table>"; /* What I want to see: <table border='1'> <tr> <td>0</td> <td>1</td> <td>2</td> <td>3</td> </tr> <tr> <td>-</td> <td>1000</td> <td>-</td> <td>1500</td> </tr> </table> */ ?>

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  • foreign key constraints on primary key columns - issues ?

    - by zzzeek
    What are the pros/cons from a performance/indexing/data management perspective of creating a one-to-one relationship between tables using the primary key on the child as foreign key, versus a pure surrogate primary key on the child? The first approach seems to reduce redundancy and nicely constrains the one-to-one implicitly, while the second approach seems to be favored by DBAs, even though it creates a second index: create table parent ( id integer primary key, data varchar(50) ) create table child ( id integer primary key references parent(id), data varchar(50) ) pure surrogate key: create table parent ( id integer primary key, data varchar(50) ) create table child ( id integer primary key, parent_id integer unique references parent(id), data varchar(50) ) the platforms of interest here are Postgresql, Microsoft SQL Server.

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  • SQL Server INSERT, Scope_Identity() and physical writing to disc

    - by TheBlueSky
    Hello everyone, I have a stored procedure that does, among other stuff, some inserts in different table inside a loop. See the example below for clearer understanding: INSERT INTO T1 VALUES ('something') SET @MyID = Scope_Identity() ... some stuff go here INSERT INTO T2 VALUES (@MyID, 'something else') ... The rest of the procedure These two tables (T1 and T2) have an IDENTITY(1, 1) column in each one of them, let's call them ID1 and ID2; however, after running the procedure in our production database (very busy database) and having more than 6250 records in each table, I have noticed one incident where ID1 does not match ID2! Although normally for each record inserted in T1, there is record inserted in T2 and the identity column in both is incremented consistently. The "wrong" records were something like that: ID1 Col1 ---- --------- 4709 data-4709 4710 data-4710 ID2 ID1 Col1 ---- ---- --------- 4709 4710 data-4709 4710 4709 data-4710 Note the "inverted", ID1 in the second table. Knowing not that much about SQL Server underneath operations, I have put the following "theory", maybe someone can correct me on this. What I think is that because the loop is faster than physically writing to the table, and/or maybe some other thing delayed the writing process, the records were buffered. When it comes the time to write them, they were wrote in no particular order. Is that even possible if no, how to explain the above mentioned scenario? If yes, then I have another question to rise. What if the first insert (from the code above) got delayed? Doesn't that mean I won't get the correct IDENTITY to insert into the second table? If the answer of this is also yes, what can I do to insure the insertion in the two tables will happen in sequence with the correct IDENTITY? I appreciate any comment and information that help me understand this. Thanks in advance.

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  • html clickable layout area. best practice

    - by Andrew Florko
    I am bad in html layout but I have to produce it :) I want to make big button on a page that is implemented as div with children tags (maybe - a bad idea). I can handle click event on boundary-div with javascript but it requires javascript enabled. I can wrap boundary-div with "anchor" tag but is doesn't work in IE Please, suggest me the best way to implement this. <a href="..."> <table> <td> ... </td> <td> ... <table> ... </table> </td> </table> </a>

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  • A good approach to db planing for reporting service

    - by Itay Moav
    The scenario: Big system (~200 tables). 60,000 users. Complex reports that will require me to do multiple queries for each report and even those will be complex queries with inner queries all over the place + some processing in PHP. I have seen an approach, which I am not sure about: Having one centralized, de-normalized, table that registers any activity in the system which is reportable. This table will hold mostly foreign keys, so she should be fairly compact and fast. So, for example (My system is a virtual learning management system), A user enrolls to course, the table stores the user id, date, course id, organization id, activity type (enrollment). Of course I also store this data in a normalized DB, which the actual application uses. Pros I see: easy, maintainable queries and code to process data and fast retrieval. Cons: there is a danger of the de-normalized table to be out of sync with the real DB. Is this approach worth considering, or (preferably from experience) is total $#%#%t?

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  • jQuery animation if load() returns something different...

    - by Dan LaManna
    setInterval(function() { var prevTopArticle = $("#toparticles table:first").html(); $("#toparticles").load("myurloffeed.com/topfeed", function() { alternateBG(); var newTopArticle = $("#toparticles table:first").html(); if (prevTopArticle!=newTopArticle) { $("#toparticles table:first").effect("highlight", {color:"#faffc4"}, 2000); } }); }, 8000); So it sets the current first table item to a variable, loads the toparticles div with the tables off the url, and if they are different it will perform the highlight effect, however it does the highlight effect anyway, completely unsure why it isn't working.

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  • Oracle/c#: How do i use bind variables with select statements to return multiple records?

    - by twiga
    I have a question regarding Oracle bind variables and select statements. What I would like to achieve is do a select on a number different values for the primary key. I would like to pass these values via an array using bind values. select * from tb_customers where cust_id = :1 int[] cust_id = { 11, 23, 31, 44 , 51 }; I then bind a DataReader to get the values into a table. The problem is that the resulting table only contains a single record (for cust_id=51). Thus it seems that each statement is executed independently (as it should), but I would like the results to be available as a collective (single table). A workaround is to create a temporary table, insert all the values of cust_id and then do a join against tb_customers. The problem with this approach is that I would require temporary tables for every different type of primary key, as I would like to use this against a number of tables (some even have combined primary keys). Is there anything I am missing?

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  • User settings mechanism for Yii

    - by Peterim
    Hi guys! I need some help with user settings mechanism for my Yii-based application. I've created the following db structure to store user settings: table user with the following fields id | username | email | etc. table settingslist (to store a list of all possible settings with descriptions) with the following fields id | code | name | description table settings (to store all user settings) with the following fields id | userid | settingslistcode | value Now I'm stuck with the form which allows user to change his settings. I had to deal before with the regular models (i.e. for posts, comments, etc.) where every new model had only one row in the database (Post model - id | title | body |) with the certain amount of attributes (fields of the table). But now I need to store user settings in 10-15 rows and I don't know how to apply Yii model mechanism to work with this, so I can retrieve those settings in a single form (so user could change his preferences). Any suggestions are greatly appreciated. Thank you!

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  • How can I improve the performance of LinqToSql queries that use EntitySet properties?

    - by DanM
    I'm using LinqToSql to query a small, simple SQL Server CE database. I've noticed that any operations involving sub-properties are disappointingly slow. For example, if I have a Customer table that is referenced by an Order table, LinqToSql will automatically create an EntitySet<Order> property. This is a nice convenience, allowing me to do things like Customer.Order.Where(o => o.ProductName = "Stopwatch"), but for some reason, SQL Server CE hangs up pretty bad when I try to do stuff like this. One of my queries, which isn't really that complicated takes 3-4 seconds to complete. I can get the speed up to acceptable, even fast, if I just grab the two tables individually and convert them to List<Customer> and List<Order>, then join then manually with my own query, but this is throwing out a lot of what makes LinqToSql so appealing. So, I'm wondering if I can somehow get the whole database into RAM and just query that way, then occasionally save it. Is this possible? How? If not, is there anything else I can do to boost the performance besides resorting to doing all the joins manually? Note: My database in its initial state is about 250K and I don't expect it to grow to more than 1-2Mb. So, loading the data into RAM certainly wouldn't be a problem from a memory point of view. Update Here are the table definitions for the example I used in my question: create table Order ( Id int identity(1, 1) primary key, ProductName ntext null ) create table Customer ( Id int identity(1, 1) primary key, OrderId int null references Order (Id) )

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  • Comparing an id to id of different tables rows mysql

    - by jett
    So I am trying to retrieve all interests from someone, and be able to list them. This works with the following query. SELECT *,( SELECT GROUP_CONCAT(interest_id SEPARATOR ",") FROM people_interests WHERE person_id = people.id ) AS interests FROM people WHERE id IN ( SELECT person_id FROM people_interests WHERE interest_id = '.$site->db->clean($_POST['showinterest_id']).' ) ORDER BY lastname, firstname In this one which I am having trouble with, I want to select only those who happen to have their id in the table named volleyballplayers. The table just has an id, person_id, team_id, and date fields. SELECT *,( SELECT GROUP_CONCAT(interest_id SEPARATOR ",") FROM people_interests WHERE person_id = people.id ) AS interests FROM people WHERE id IN ( SELECT person_id FROM people_interests WHERE volleyballplayers.person_id = person_id ) ORDER BY lastname, firstname I just want to make sure that only the people who are in the volleyballplayers table show up, but I am getting an error saying that Unknown column 'volleyballplayers.person_id' in 'where clause' although I am quite sure of the name of table and I know the column is named person_id.

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  • LinqToSQL: Not possible to update PrimaryKey?

    - by Zuhaib
    I have a simple table (lets call it Table1) that has a NVARCHAR field as the PK. Table1 has no association with any other tables. When I update Table1's PK column using LinqToSQL it fails. If I update other column it succeeds. I could delete this row and insert new one in Table1, but I don't want to. There is a transaction table which has Table1's PK column as a column. When the PK of Table1 is changed I want no effect in the transaction table. But when the row from Table1 is deleted, I want the transaction rows to be deleted. The cascading is done via Trigger. As there is not association between these two tables, if I update the PK column of Table1 using normal SQL, it works and there is no effect on the transaction table as expected. When I delete the row the trigger deletes the rows from transaction table. For this reason I can't delete and then add new row in Table1. So what can be done to successfully update the PrimaryKey of the Table1?

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  • NES Programming - Nametables?

    - by Jeffrey Kern
    Hello everyone, I'm wondering about how the NES displays its graphical muscle. I've researched stuff online and read through it, but I'm wondering about one last thing: Nametables. Basically, from what I've read, each 8x8 block in a NES nametable points to a location in the pattern table, which holds graphic memory. In addition, the nametable also has an attribute table which sets a certain color palette for each 16x16 block. They're linked up together like this: (assuming 16 8x8 blocks) Nametable, with A B C D = pointers to sprite data: ABBB CDCC DDDD DDDD Attribute table, with 1 2 3 = pointers to color palette data, with < referencing value to the left, ^ above, and ' to the left and above: 1<2< ^'^' 3<3< ^'^' So, in the example above, the blocks would be colored as so 1A 1B 2B 2B 1C 1D 2C 2C 3D 3D 3D 3D 3D 3D 3D 3D Now, if I have this on a fixed screen - it works great! Because the NES resolution is 256x240 pixels. Now, how do these tables get adjusted for scrolling? Because Nametable 0 can scroll into Nametable 1, and if you keep scrolling Nametable 0 will wrap around again. That I get. But what I don't get is how to scroll the attribute table wraps around as well. From what I've read online, the 16x16 blocks it assigns attributes for will cause color distortions on the edge tiles of the screen (as seen when you scroll left to right and vice-versa in SMB3). The concern I have is that I understand how to scroll the nametables, but how do you scroll the attribute table? For intsance, if I have a green block on the left side of the screen, moving the screen to right should in theory cause the tiles to the right to be green as well until they move more into frame, to which they'll revert to their normal colors.

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  • Accessing Element Count and Values Within a Hidden Div

    - by Tegan Snyder
    I'm having trouble grabbing the TR count in JQuery of a table that inside a DIV set to be hidden. Here is an example: <div id="questions" style="display: none;"> <table id="tbl_questions"> <thead> <tr> <th>Question</th> <th>Weight</th> </tr> </thead> <tbody> <tr id="q0"> <td id="td_question0">Some Question 0</td> <td id="td_wieght0">Some Weight 0</td> </tr> <tr id="q1"> <td id="td_question1">Some Question 1</td> <td id="td_wieght1">Some Weight 1</td> </tr> </tbody> </table> </div> Note the table is within the containing div. It's set to display: none. When I try to run this JQuery code it returns 0. var question_count = $("#tbl_questions> tr").size(); alert(question_count); Any ideas? I'm try to locate the count so I can then build an array of each question and weight in the table. Since the ID's provide me with an index this should be simple, but is the fact that it is contained in a hidden DIV going to be a problem just as the above question? Thanks, Tegan Snyder

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