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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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  • Insert data in an object to a database.

    - by paul
    I am facing the following design/implementation dilemma. I have a class Customer which is below with getters and setters. I would like to insert the value of the Customer into a "Customer" table of a database. But Customer has an address which is of type "Address". How do I go about inserting this field into the database?(I am using sqlite3). I thought of writing a separate table "Address(customerId,doorNo,city,state,country,pinCode)". But I am having second thoughts about generating the primary key(customerId) which should be same for both the "customer" and "Address" table. Sqlite3 faq states that I can do "Integer Primary Key" to use the field to generate an auto number. But if I do that in customer table, I would have to retrieve the same Id to be used in Address table. This kinda looks wrong to me :-?. There should be an elegant method to solve this. Any ideas would be much appreciated. Thanks in advance. import java.io.*; import java.sql.*; class Customer { private String id; private String name; private Address address; private Connection connection; private ResultSet resultSet; private PreparedStatement preparedStatement; public void insertToDatabase(){ } } class Address{ private String doorNumber; private String streetName; private String cityName; private String districtName; private String stateName; private String countryName; private long pinCode; }

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  • How to change SRID of geometry column?

    - by Z77
    I have table where the one of columns is geometry column the_geom for polygons with SRID. I added new column in the same table with exactly the same geometry data as in the_geom. This another column has name the_geom4258 because I want here to set up another SRID=4258. So what is the procedure to set up another SRID geometry to be changed (in another coord.system)? Is just enough to apply following query: UPDATE table SET the_geom4258=ST_SetSRID(the_geom4258,4258);

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  • Refreshing metadata on user functions t-SQL

    - by luckyluke
    I am doing some T-SQL programming and I have some Views defines on my database. The data model is still changing these days and I have some table functions defined. Sometimes i deliberately use select * from MYVIEW in such a table function to return all columns. If the view changes (or table) the function crashes and I need to recompile it. I know it is in general good thing so that it prevents from hell lotta errors but still... Is there a way to write such functions so the dont' blow up in my face everytime I change something on the underlying table? Or maybe I am doing something completely wrong... Thanks for help

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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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  • 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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  • 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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  • How to write a good PHP database insert using an associative array

    - by Tom
    In PHP, I want to insert into a database using data contained in a associative array of field/value pairs. Example: $_fields = array('field1'=>'value1','field2'=>'value2','field3'=>'value3'); The resulting SQL insert should look as follows: INSERT INTO table (field1,field2,field3) VALUES ('value1','value2','value3'); I have come up with the following PHP one-liner: mysql_query("INSERT INTO table (".implode(',',array_keys($_fields)).") VALUES (".implode(',',array_values($_fields)).")"); It separates the keys and values of the the associative array and implodes to generate a comma-separated string . The problem is that it does not escape or quote the values that were inserted into the database. To illustrate the danger, Imagine if $_fields contained the following: $_fields = array('field1'=>"naustyvalue); drop table members; --"); The following SQL would be generated: INSERT INTO table (field1) VALUES (naustyvalue); drop table members; --; Luckily, multiple queries are not supported, nevertheless quoting and escaping are essential to prevent SQL injection vulnerabilities. How do you write your PHP Mysql Inserts? Note: PDO or mysqli prepared queries aren't currently an option for me because the codebase already uses mysql extensively - a change is planned but it'd take alot of resources to convert?

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  • Event feed implementation - will it scale?

    - by SlappyTheFish
    Situation: I am currently designing a feed system for a social website whereby each user has a feed of their friends' activities. I have two possible methods how to generate the feeds and I would like to ask which is best in terms of ability to scale. Events from all users are collected in one central database table, event_log. Users are paired as friends in the table friends. The RDBMS we are using is MySQL. Standard method: When a user requests their feed page, the system generates the feed by inner joining event_log with friends. The result is then cached and set to timeout after 5 minutes. Scaling is achieved by varying this timeout. Hypothesised method: A task runs in the background and for each new, unprocessed item in event_log, it creates entries in the database table user_feed pairing that event with all of the users who are friends with the user who initiated the event. One table row pairs one event with one user. The problems with the standard method are well known – what if a lot of people's caches expire at the same time? The solution also does not scale well – the brief is for feeds to update as close to real-time as possible The hypothesised solution in my eyes seems much better; all processing is done offline so no user waits for a page to generate and there are no joins so database tables can be sharded across physical machines. However, if a user has 100,000 friends and creates 20 events in one session, then that results in inserting 2,000,000 rows into the database. Question: The question boils down to two points: Is this worst-case scenario mentioned above problematic, i.e. does table size have an impact on MySQL performance and are there any issues with this mass inserting of data for each event? Is there anything else I have missed?

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  • How to map a Dictionary<string, string> spanning several tables

    - by Kim Johansson
    I have four tables: CREATE TABLE [Languages] ( [Id] INTEGER IDENTITY(1,1) NOT NULL, [Code] NVARCHAR(10) NOT NULL, PRIMARY KEY ([Id]), UNIQUE INDEX ([Code]) ); CREATE TABLE [Words] ( [Id] INTEGER IDENTITY(1,1) NOT NULL, PRIMARY KEY ([Id]) ); CREATE TABLE [WordTranslations] ( [Id] INTEGER IDENTITY(1,1) NOT NULL, [Value] NVARCHAR(100) NOT NULL, [Word] INTEGER NOT NULL, [Language] INTEGER NOT NULL, PRIMARY KEY ([Id]), FOREIGN KEY ([Word]) REFERENCES [Words] ([Id]), FOREIGN KEY ([Language]) REFERENCES [Languages] ([Id]) ); CREATE TABLE [Categories] ( [Id] INTEGER IDENTITY(1,1) NOT NULL, [Word] INTEGER NOT NULL, PRIMARY KEY ([Id]), FOREIGN KEY ([Word]) REFERENCES [Words] ([Id]) ); So you get the name of a Category via the Word - WordTranslation - Language relations. Like this: SELECT TOP 1 wt.Value FROM [Categories] AS c LEFT JOIN [WordTranslations] AS wt ON c.Word = wt.Word WHERE wt.Language = ( SELECT TOP 1 l.Id FROM [Languages] WHERE l.[Code] = N'en-US' ) AND c.Id = 1; That would return the en-US translation of the Category with Id = 1. My question is how to map this using the following class: public class Category { public virtual int Id { get; set; } public virtual IDictionary<string, string> Translations { get; set; } } Getting the same as the SQL query above would be: Category category = session.Get<Category>(1); string name = category.Translations["en-US"]; And "name" would now contain the Category's name in en-US. Category is mapped against the Categories table. How would you do this and is it even possible?

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  • temporary tables within stored procedures on slave servers with readonly set

    - by lau
    Hi, We have set up a replication scheme master/slave and we've had problems lately because some users wrote directly on the slave instead of the master, making the whole setup inconsistent. To prevent these problems from happening again, we've decided to remove the insert, delete, update, etc... rights from the users accessing the slave. Problems is that some stored procedure (for reading) require temporary tables. I read that changing the global variable read_only to true would do what I want and allow the stored procedures to work correctly ( http://dev.mysql.com/doc/refman/5.0/en/server-system-variables.html#sysvar_read_only ) but I keep getting the error : The MySQL server is running with the --read-only option so it cannot execute this statement (1290) The stored procedure that I used (for testing purpose) is this one : DELIMITER $$ DROP PROCEDURE IF EXISTS test_readonly $$ CREATE DEFINER=dbuser@% PROCEDURE test_readonly() BEGIN CREATE TEMPORARY TABLE IF NOT EXISTS temp ( BT_INDEX int(11), BT_DESC VARCHAR(10) ); INSERT INTO temp (BT_INDEX, BT_DESC) VALUES (222,'walou'), (111,'bidouille'); DROP TABLE temp; END $$ DELIMITER ; The create temporary table and the drop table work fine with the readonly flag - if I comment the INSERT line, it runs fine- but whenever I want to insert or delete from that temporary table, I get the error message. I use Mysql 5.1.29-rc. My default storage engine is InnoDB. Thanks in advance, this problem is really driving me crazy.

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  • any suggestions on this css print problem

    - by user225269
    I have this code on my print.css: #header, #tae, #nav, .noprint {display: none;} width: 100%; margin: 0; float: none; In order not to display the elements within those div tags. But I don't know with the code below why it isn't cooperating. If I place the div tags on it. And then I hit the print button. I see no output. Here it is: <div id="tae"> <table border="0" align="center" cellpadding="0" cellspacing="0" class="bg1"> <tr> <td class="text1" style="height: 50px;">xd627 information management system</td> </tr> <tr> <td class="bg5"><table border="0" cellspacing="0" cellpadding="0" style="height: 62px; padding-top: 15px;"> <tr align="center"> <td><a href="userpage.php" class="link1">Homepage</a></td> <td><a href="RegStuds.php" class="link1">Database</a></td> <td><a href="#" class="link1">About</a></td> <td>&nbsp;</td> <td>&nbsp;</td> <td>&nbsp;</td> </tr> </table></td> </tr> <tr> <td valign="top" class="bg6">&nbsp;</td> </tr> <tr> <td><table width="780" border="0" cellspacing="0" cellpadding="0"> <tr valign="top"> <td width="20">&nbsp;</td> <td width="297"><table width="100%" border="0" cellspacing="0" cellpadding="0"> <tr> <td><img src="images/spacer.gif" alt="" width="30" height="30" /></td> </tr> </tr> <tr> <td class="text2"> </div> <div id="max"> <?php //some php code in here showing a mysql table. ?> </div> What's wrong with my code? Does the php script depend on the one where I put the div tag in? What do I do? All I want to show up in my page when printed is the mysql table. I'm using Universal Document Converter to simulate printing.

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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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  • MySQL Need some help with a query

    - by Jules
    I'm trying to fix some data by adding a new field. I have a backup from a few months ago and I have restored this database to my server. I'm looking at table called pads, its primary key is PadID and the field of importance is called RemoveMeDate. In my restored (older) database there is less records with an actual date set in RemoveMeDate. My control date is 2001-01-01 00:00:00 meaning that the record is not hidden aka visible. What I need to do is select all the records from the older database / table with the control date and join with those from the newer db /table where the control date is not set. I hope I've explained that correctly. I'll try again, with numbers. I have 80,000 visible records in the older table (with control date set) and 30,000 in the newer db/table. I need to select the 50,000 from the old database, to perform an update query. Heres my query, which I'd can't get to work as I'd like. jules-fix-reasons is the old database, jules is the newer one. select p.padid from `jules-fix-reasons`.`pads` p JOIN `jules`.`pads` ON p.padid = `jules`.`pads`.`PadID` where p.RemoveMeDate <> '2001-01-01 00:00:00' AND `jules`.`pads`.RemoveMeDate = '2001-01-01 00:00:00'

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  • MySQL won't use index for query?

    - by Jack Sleight
    I have this table: CREATE TABLE `point` ( `id` INT(11) NOT NULL AUTO_INCREMENT, `siteid` INT(11) NOT NULL, `lft` INT(11) DEFAULT NULL, `rgt` INT(11) DEFAULT NULL, `level` SMALLINT(6) DEFAULT NULL, PRIMARY KEY (`id`), KEY `point_siteid_site_id` (`siteid`), CONSTRAINT `point_siteid_site_id` FOREIGN KEY (`siteid`) REFERENCES `site` (`id`) ON DELETE CASCADE ) ENGINE=INNODB AUTO_INCREMENT=35 DEFAULT CHARSET=utf8 COLLATE=utf8_unicode_ci And this query: SELECT * FROM `point` WHERE siteid = 1; Which results in this EXPLAIN information: +----+-------------+-------+------+----------------------+------+---------+------+------+-------------+ | id | select_type | table | type | possible_keys | key | key_len | ref | rows | Extra | +----+-------------+-------+------+----------------------+------+---------+------+------+-------------+ | 1 | SIMPLE | point | ALL | point_siteid_site_id | NULL | NULL | NULL | 6 | Using where | +----+-------------+-------+------+----------------------+------+---------+------+------+-------------+ Question is, why isn't the query using the point_siteid_site_id index?

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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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  • 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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  • Google Visualization Annotated Time Line, removing data points.

    - by Vitaly Babiy
    I am trying to build a graph that will change resolution depending on how far you are zoomed in. Here is what it looks like when you are complete zoomed out. So this looks good so when I zoom in I get a higher resolution data and my graph looks like this: The problem is when I zoom out the higher resolution data does not get cleared out of the graph: The tables below the graphs are table display what is in the DataTable. This is what drawing code looks like. var g_graph = new google.visualization.AnnotatedTimeLine(document.getElementById('graph_div_json')); var table = new google.visualization.Table(document.getElementById('table_div_json')); function handleQueryResponse(response){ log("Drawing graph") var data = response.getDataTable() g_graph.draw(data, {allowRedraw:true, thickness:2, fill:50, scaleType:'maximized'}) table.draw(data, {allowRedraw:true}) } I am try to find a way for it to only displaying the data that is in the DataTable. I have tried removing the allowRedraw flag but then it breaks the zooming operation. Any help would be greatly appreciated. Thanks

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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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  • Data retrieval and Join operations with cluster db server

    - by Goerge
    If any database spreads across multiple servers (ex. Microsoft Sql Server), how can we do join or filter operations. In my scenario, if suppose: A single table spreads across multiple servers how can we filter rows based on user input? If master table is there on one db server and transaction table is at another db server, how can we do join operations? Please let me know how can we achieve this and where can I get more details about this?

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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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  • 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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  • Exporting de-aggregated data

    - by Ben
    I'm currently working on a data export feature for a survey application. We are using SQL2k8. We store data in a normalized format: QuestionId, RespondentId, Answer. We have a couple other tables that define what the question text is for the QuestionId and demographics for the RespondentId... Currently I'm using some dynamic SQL to generate a pivot that joins the question table to the answer table and creates an export, its working... The problem is that it seems slow and we don't have that much data (less than 50k respondents). Right now I'm thinking "why am I 'paying' to de-aggregate the data for each query? Why don't I cache that?" The data being exported is based on dynamic criteria. It could be "give me respondents that completed on x date (or range)" or "people that like blue", etc. Because of that, I think I have to cache at the respondent level, find out what respondents are being exported and then select their combined cached de-aggregated data. To me the quick and dirty fix is a totally flat table, RespondentId, Question1, Question2, etc. The problem is, we have multiple clients and that doesn't scale AND I don't want to have to maintain the flattened table as the survey changes. So I'm thinking about putting an XML column on the respondent table and caching the results of a SELECT * FROM Data FOR XML AUTO WHERE RespondentId = x. With that in place, I would then be able to get my export with filtering and XML calls into the XML column. What are you doing to export aggregated data in a flattened format (CSV, Excel, etc)? Does this approach seem ok? I worry about the cost of XML functions on larger result sets (think SELECT RespondentId, XmlCol.value('//data/question_1', 'nvarchar(50)') AS [Why is there air?], XmlCol.RinseAndRepeat)... Is there a better technology/approach for this? Thanks!

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  • Handling auto-incrementing IDENTITY SQL Server fields with LINQ to SQL in C#

    - by Maxim Z.
    I'm building an ASP.NET MVC site that uses LINQ to SQL to connect to SQL Server, where I have a table that has an IDENTITY bigint primary key column that represents an ID. In one of my code methods, I need to create an object of that table to get its ID, which I will place into another object based on another table (FK-to-PK relationship). At what point is the IDENTITY column value generated and how can I obtain it from my code? Is the right approach to: Create the object that has the IDENTITY column Do an InsertOnSubmit() and SubmitChanges() to submit the object to the database table Get the value of the ID property of the object

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  • "Special case" records for foreign key constraints

    - by keithjgrant
    Let's say I have a mysql table, called foo with a foreign key option_id constrained to the option table. When I create a foo record, the user may or may not have selected an option, and 'no option' is a viable selection. What is the best way to differentiate between 'null' (i.e. the user hasn't made a selection yet) and 'no option' (i.e. the user selected 'no option')? Right now, my plan is to insert a special record into the option table. Let's say that winds up with an id of 227 (this table already has a number of records at this point, so '1' isn't available). I have no need to access this record at a database level, and it would act as nothing more than a placeholder that the foreign key in the foo table can reference. So do I just hard-code '227' in my codebase when I'm creating 'foo' records where the user has selected 'no option'? The hard-coded id seems sloppy, and leaves room for error as the code is maintained down the road, but I'm not really sure of another approach.

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