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  • Relational databases are not suited for my application - what's the alternative?

    - by waitinforatrain
    Hi, I'm writing a CMS in PHP that allows the user to define different fields (e.g. a Blog page could have fields for Title (string), Content (rich text), Picture (file)). I need the user to be able to add and remove fields dynamically, and the only way I can think of to do it with relational DBs is to serialise all these values and store them in one cell. This seems like a slow approach and like I'm trying to fit something dynamic within a static structure. Could someone recommend anything that is PHP-compatible that would make this easier?

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  • Multiple conditions with CASE statements

    - by Pavan Reddy
    I need to query some data. here is the query that i have constructed but which isn't workig fine for me. For this example I am using AdventureWorks database. SELECT * FROM [Purchasing].[Vendor] WHERE PurchasingWebServiceURL LIKE case // In this case I need all rows to be returned if @url is '' or 'ALL' or NULL when (@url IS null OR @url = '' OR @url = 'ALL') then ('''%'' AND PurchasingWebServiceURL IS NULL') //I need all records which are blank here including nulls when (@url = 'blank') then (''''' AND PurchasingWebServiceURL IS NULL' ) //n this condition I need all record which are not like a particular value when (@url = 'fail') then ('''%'' AND PurchasingWebServiceURL NOT LIKE ''%treyresearch%''' ) //Else Match the records which are `LIKE` the input value else '%' + @url + '%' end This is not working for me. How can I have multiple where condition clauses in the THEN of the the same CASE? How can I make this work?

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  • How would I associate a "Note" class to 4+ classes without creating lookup table for each associatio

    - by Gthompson83
    Im creating a project tasklist application. I have project, section, task, issue classes, and would like to use one class to be able to add simple notes to any object instance of those classes. The task, issue tables both use a standard identity field as a primary key. The section table has a two field primary key. The project table has a single int primary key defined by the user. Is there a way to associate the note class with each of these without using a seperate lookup table for each class? I'm not so sure my original idea is a decent way to implement this. I considered the following (each variable mapping to a field n the notes table. Private _NoteId As Integer Private _ProjectId As Integer Private _SectionId As Integer Private _SectionId2 As Integer Private _TaskId As Integer Private _IssueId As Integer Private _Note As String Private _UserId As Guid Then I would be able to write seperate methods (getProjectNotes, getTaskNotes) to get notes attached to each class. I started writing this a few weeks ago but got pulled away before i could finish. When revisiting this code today my first thought "this is retarded". Thoughts on drawbacks to this design?

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  • Why would using a Temp table be faster than a nested query?

    - by Mongus Pong
    We are trying to optimise some of our queries. One query is doing the following: SELECT t.TaskID, t.Name as Task, '' as Tracker, t.ClientID, (<complex subquery>) Date, INTO [#Gadget] FROM task t SELECT TOP 500 TaskID, Task, Tracker, ClientID, dbo.GetClientDisplayName(ClientID) as Client FROM [#Gadget] order by CASE WHEN Date IS NULL THEN 1 ELSE 0 END , Date ASC DROP TABLE [#Gadget] (I have removed the complex subquery, cos I dont think its relevant other than to explain why this query has been done as a two stage process.) Now I would have thought it would be far more efficient to merge this down into a single query using subqueries as : SELECT TOP 500 TaskID, Task, Tracker, ClientID, dbo.GetClientDisplayName(ClientID) FROM ( SELECT t.TaskID, t.Name as Task, '' as Tracker, t.ClientID, (<complex subquery>) Date, FROM task t ) as sub order by CASE WHEN Date IS NULL THEN 1 ELSE 0 END , Date ASC This would give the optimiser better information to work out what was going on and avoid any temporary tables. It should be faster. But it turns out it is a lot slower. 8 seconds vs under 5 seconds. I cant work out why this would be the case as all my knowledge of databases imply that subqueries would always be faster than using temporary tables. Can anyone explain what could be going on!?!?

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  • 100+ tables to joined

    - by deian
    Hi guys, I was wondering if anyone ever had a change to measure how a would 100 joined tables perform? Each table would have an ID column with primary index and all table are 1:1 related. It is a common problem within many data entry applications where we need to collect 1000+ data points. One solution would be to have one big table with 1000+ columns and the alternative would be to split them into multiple tables and join them when it is necessary. So perhaps more real question would be how 30 tables (30 columns each) would behave with multitable join. 500K-1M rows should be the expected size of the tables. Cheers

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  • How to verify if two tables have exactly the same data?

    - by SiLent SoNG
    Basically we have one table (original table) and it is backed up into another table (backup table); thus the two tables have exactly the same schema. At the beginning both tables (original table and backup table) contains exactly the same set of data. After sometime for some reason I need to verify whether dataset in the original table has changed or not. In order to do this I have to compare the dataset in the original table against the backup table. Let's say the original table has the following schema: `create table LemmasMapping ( lemma1 int, lemma2 int, index ix_lemma1 using btree (lemma1), index ix_lemma2 using btree (lemma2) )` How could I achieve the dataset comparision? Update: the table does not have a primary key. It simply stores mappings between two ids.

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  • Can't delete record via the datacontext it was retrieved from

    - by Antilogic
    I just upgraded one of my application's methods to use compiled queries (not sure if this is relevant). Now I'm getting contradicting error messages when I run the code. This is my method: MyClass existing = Queries.MyStaticCompiledQuery(MyRequestScopedDataContext, param1, param2).SingleOrDefault(); if (existing != null) { MyRequestScopedDataContext.MyClasses.DeleteOnSubmit(existing); } When I run it I get this message: Cannot remove an entity that has not been attached. Note that the compiled query and the DeleteOnSubmit reference the same DataContext. Still I figured I'd humor the application and add an attach command before the DeleteOnSubmit, like so: MyClass existing = Queries.MyStaticCompiledQuery(MyRequestScopedDataContext, param1, param2).SingleOrDefault(); if (existing != null) { MyRequestScopedDataContext.MyClasses.Attach(existing); MyRequestScopedDataContext.MyClasses.DeleteOnSubmit(existing); } BUT... When I run this code, I get a completely different contradictory error message: An attempt has been made to Attach or Add an entity that is not new, perhaps having been loaded from another DataContext. This is not supported. I'm at a complete loss... Does anyone else have some insight as to why I can't delete a record via the same DataContext I retrieved it from?

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  • How to use a varying database?

    - by nimo
    I want to use a database which name is stored in a variable. How do I do this? I first thought this would work but it doesn't: exec('use '+@db) That will not change database context Suggestions anyone?

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  • Generating a set of files containing dumps of individual tables in a way that guarantees database co

    - by intuited
    I'd like to dump a MySQL database in such a way that a file is created for the definition of each table, and another file is created for the data in each table. I'd like this to be done in a way that guarantees database integrity by locking the entire database for the duration of the dump. What is the best way to do this? Similarly, what's the best way to lock the database while restoring a set of these dump files? edit I can't assume that mysql will have permission to write to files.

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  • best database design for city zip & state tables

    - by ryan a
    My application will need to reference addresses. Street info will be stored with my main objects but the rest needs to be stored seperately to reduce redundancy. How should I store/retrieve ZIPs, cities and states? Here are some of my ideas. single table solution (cant do relationships) [locations] locationID locationParent (FK for locationID - 0 for state entries) locationName (city, state) locationZIP two tables (with relationships, FK constraints, ref integrity) [state] stateID stateName [city] cityID stateID (FK for state.stateID) cityName zipCode three tables [state] stateID stateName [city] cityID stateID (FK for state.stateID) cityName [zip] zipID cityID (FK for city.cityID) zipName Then I read into ZIP codes amd how they are assigned. They aren't specifically related to cities. Some cities have more than one ZIP (ok will still work) but some ZIPs are in more than one city (oh snap) and some other ZIPs (very few) are in more than one state! Also some ZIPs are not even in the same state as the address they belong to at all. Seems ZIPs are made for carrier route identification and some remote places are best served by post offices in neighboring cities or states. Does anybody know of a good (not perfect) solution that takes this into consideration to minimize discrepencies as the database grows?

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  • LESS THAN OR EQUAL TO IN Oracle SQL

    - by Jasim
    updated_date = 08-Jun-2010; I have a query like this select * from asd whre updated_date <= todate('08-Jun-2010', 'dd-MM-yy'); but i am not getting any result. it is wotking only if todate is 09-Jun-2010... ie my equalto operator is not working properly. y is it like that ny help?

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  • Syntax error in INSERT INTO statement

    - by user454563
    I wrote a program that connects to MS Access. When I fill in the fields and add a new item to Access the program fails. The exception is "Syntax error in INSERT INTO statement" Here is the relevant code. **************************************************************** AdoHelper.cs **************************************************************** using System; using System.Collections.Generic; using System.Text; using System.Data; using System.Data.OleDb; namespace Yad2 { class AdoHelper { //get the connection string from the app.config file //Provider=Microsoft.ACE.OLEDB.12.0;Data Source=|DataDirectory|\Yad2.accdb static string connectionString = Properties.Settings.Default.DBConnection.ToString(); //declare the db connection static OleDbConnection con = new OleDbConnection(connectionString); /// <summary> /// To Execute queries which returns result set (table / relation) /// </summary> /// <param name="query">the query string</param> /// <returns></returns> public static DataTable ExecuteDataTable(string query) { try { con.Open(); OleDbCommand command = new OleDbCommand(query, con); System.Data.OleDb.OleDbDataAdapter tableAdapter = new System.Data.OleDb.OleDbDataAdapter(command); DataTable dt = new DataTable(); tableAdapter.Fill(dt); return dt; } catch (Exception ex) { throw ex; } finally { con.Close(); } } /// <summary> /// To Execute update / insert / delete queries /// </summary> /// <param name="query">the query string</param> public static void ExecuteNonQuery(string query) { try { con.Open(); System.Data.OleDb.OleDbCommand command = new System.Data.OleDb.OleDbCommand(query, con); command.ExecuteNonQuery(); } catch (Exception ex) { throw ex; } finally { con.Close(); } } /// <summary> /// To Execute queries which return scalar value /// </summary> /// <param name="query">the query string</param> public static object ExecuteScalar(string query) { try { con.Open(); System.Data.OleDb.OleDbCommand command = new System.Data.OleDb.OleDbCommand(query, con); /// here is the Excaption !!!!!!!!! return command.ExecuteScalar(); } catch { throw; } finally { con.Close(); } } } } **************************************************************************** **************************************************************************** DataQueries.cs **************************************************************************** using System; using System.Collections.Generic; using System.Text; using System.Data; namespace Yad2 { class DataQueries { public static DataTable GetAllItems() { try { string query = "Select * from Messages"; DataTable dt = AdoHelper.ExecuteDataTable(query); return dt; } catch (Exception ex) { throw ex; } } public static void AddNewItem(string mesNumber, string title , string mesDate , string contactMail , string mesType , string Details ) { string query = "Insert into Messages values(" + mesNumber + " , '" + title + "' , '" + mesDate + "' , '" + contactMail + "' , , '" + mesType + "' , '" + Details + "')"; AdoHelper.ExecuteNonQuery(query); } public static void DeleteDept(int mesNumber) { string query = "Delete from Item where MessageNumber=" + mesNumber; AdoHelper.ExecuteNonQuery(query); } } } *********************************************************************************************** plase help me .... why the program falls ?

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  • Update database in asp.net not working

    - by Badescu Alexandru
    Hello ! i have in asp.net a few textboxes and i wish to update my database with the values that they encapsulate . The problem is that it doesn't work and although it doesn't work, the syntax seems correct and there are no errors present . Here is my linkbutton : <asp:linkbutton id="clickOnSave" runat="server" onclick="Save_Click" Text="Save Profile" /> and my update function protected void Save_Click(object sender, EventArgs e) { SqlConnection con = new System.Data.SqlClient.SqlConnection(); con.ConnectionString = "DataSource=.\\SQLEXPRESS;AttachDbFilename=C:\\Users\\alex\\Documents\\seeubook_db.mdf;Integrated Security=True;Connect Timeout=30;User Instance=True"; con.Open(); String commandString = "UPDATE users SET last_name='" + Text4.Text.Trim() + "' , first_name='" + Textbox1.Text.Trim() + "' , about_me='" + Textbox5.Text.Trim() + "' , where_i_live='" + Textbox2.Text.Trim() + "' , where_i_was_born='" + Textbox3.Text.Trim() + "' , work_place='" + Textbox4.Text.Trim() + "' WHERE email='" + Session["user"] + "'"; SqlCommand sqlCmd = new SqlCommand(commandString, con); sqlCmd.ExecuteNonQuery(); con.Close(); }

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  • How can I bind an Enum to a DbType of bit or int?

    - by uriDium
    Hi I am using Linq2Sql and want to bind an objects field (which is enum) to either a bit or a int type in the database. For example I want have a gender field in my model. I have already edited the DBML and changed the Type to point to my enum. I want to create Radio buttons (which I think I have figured out) for gender and dropdown lists for other areas using the same idea. My enum looks like this public enum Gender { Male, Female } Mapping between DbType 'int' and Type 'Project.Models.Gender' in Column 'Gender' of Type 'Candidate' is not supported. Any ideas on how to do this mapping. Am I missing something on the enums.

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  • Joining 3 tables - doing joins how to

    - by Kieran
    This is my current query - its not getting the required result. I want it do display all of the "resources" even if they dont have a connection. SELECT * FROM (`user_permissions`) JOIN `user_groups` ON `user_groups`.`id` = `user_permissions`.`role` JOIN `user_resources` ON `user_resources`.`id` = `user_permissions`.`resource` WHERE `role` = '4' When I try left join or right join it still returns the same result. The result I get is: id | role | resource | name 5 | 4 | 2 | Changelog I want id | role | resource | name 5 | 4 | 2 | Changelog null | null | null | Resource2 null | null | null | Resource3 Is this possible?

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  • fastest way to copy a table in mysql

    - by Anon
    which one is the fastest way to completely copy a table on mysql ? CREATE TABLE copy LIKE original; INSERT INTO copy SELECT * FROM original; or CREATE TABLE copy SELECT * FROM original; ALTER TABLE copy ADD PRIMARY KEY (id); or theres another way ? PS. can't use command-line tools like mysqldump, must be on-the-fly.

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  • Microsoft Small Business Licensing Kick Start

    - by regex
    I seem to recall hearing at some point (I believe it was MIX09) that Microsoft has a licensing model of some sort where a business can consume licenses for up to two years, free of charge, until they reach a point where they are stable position and can pay their licensing at the end of two years. However, I can't find information regarding it online. I want to say that possibly stackoverflow used this licensing model to kick start their site. Is anyone familiar with this?

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  • SSRS 2005 Keep textbox and textfield together when page break occurs

    - by EKet
    Problem I don't have a details row or anything. I have simply a body and I dragged on textboxes for labeling textfields from my dataset. The problem is when one of the fields has too much data for the current page, it "page-breaks" at the start of the field leaving the textbox (label for the field) behind on the previous page. What I've tried Put the data field and the textbox label a) inside a rectangle - didn't work b) inside a list and the list inside a rectangle - didn't work c) inside a list with keep together property set to TRUE or FALSE - didn't work Question How would I group the textbox and the textfield so that regardless of where the pagebreak happens it includes its label?

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  • Tricky SQL query - need to get time frames

    - by Andrew
    I am stumbled upon a problem, when I need a query which will produce a list of speeding time frames. Here is the data example [idgps_unit_location] [dt] [idgps_unit] [lat] [long] [speed_kmh] 26 10/18/2012 18:53 2 47 56 30 27 10/18/2012 18:53 2 49 58 31 28 10/18/2012 18:53 2 28 37 15 29 10/18/2012 18:54 2 56 65 33 30 10/18/2012 18:54 2 152 161 73 31 10/18/2012 18:55 2 134 143 64 32 10/18/2012 18:56 2 22 31 12 36 10/18/2012 18:59 2 98 107 47 37 10/18/2012 18:59 2 122 131 58 38 10/18/2012 18:59 2 91 100 44 39 10/18/2012 19:00 2 190 199 98 40 10/18/2012 19:01 2 194 203 101 41 10/18/2012 19:02 2 182 191 91 42 10/18/2012 19:03 2 162 171 78 43 10/18/2012 19:03 2 174 183 83 44 10/18/2012 19:04 2 170 179 81 45 10/18/2012 19:05 2 189 198 97 46 10/18/2012 19:06 2 20 29 10 47 10/18/2012 19:07 2 158 167 76 48 10/18/2012 19:08 2 135 144 64 49 10/18/2012 19:08 2 166 175 79 50 10/18/2012 19:09 2 9 18 5 51 10/18/2012 19:09 2 101 110 48 52 10/18/2012 19:09 2 10 19 7 53 10/18/2012 19:10 2 32 41 20 54 10/18/2012 19:10 1 54 63 85 55 10/19/2012 19:11 2 55 64 50 I need a query that would convert this table into the following report that shows frames of time when speed was 80: [idgps_unit] [dt_start] [lat_start] [long_start] [speed_start] [dt_end] [lat_end] [long_end] [speed_end] [speed_average] 2 10/18/2012 19:00 190 199 98 10/18/2012 19:02 182 191 91 96.66666667 2 10/18/2012 19:03 174 183 83 10/18/2012 19:05 189 198 97 87 1 10/18/2012 19:10 54 63 85 10/18/2012 19:10 54 63 85 85 Now, what have I tried? I tried putting this into separate tables, queries and do some joins... Nothing works and I am very frustrated... I am not even sure if this could be done via the query. Asking for the expert help!

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  • Basic Hibernate question using and sql query

    - by Aerosteak
    Hello Sorry if this is basic but I cannot find the solution anywhere. I have an java Object ‘Person’ with 3 properties firstname,lastname and username. I have an Oracle Store procedure returning a Resultset with the 3 column. All works fine for that. Now I have another StoreProcedure that will only return firstname and lastname but not username. I get the following error : « could not read column value from result set username. » Hibernate tries to fetch the username property from the resultset. If I remove the property username, then it works. Do I have to Create a Special Pojo for Each type of resultset or can I tell Hibernate what to map for each result set? Please help.

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  • FluentNHibernate error -- "Invalid object name"

    - by goober
    I'm attempting to do the most simple of mappings with FluentNHibernate & Sql2005. Basically, I have a database table called "sv_Categories". I'd like to add a category, setting the ID automatically, and adding the userid and title supplied. Database table layout: CategoryID -- int -- not-null, primary key, auto-incrementing UserID -- uniqueidentifier -- not null Title -- varchar(50) -- not null Simple. My SessionFactory code (which works, as far as I can tell): _SessionFactory = Fluently.Configure().Database( MsSqlConfiguration.MsSql2005 .ConnectionString(c => c.FromConnectionStringWithKey("SVTest"))) .Mappings(x => x.FluentMappings.AddFromAssemblyOf<CategoryMap>()) .BuildSessionFactory(); My ClassMap code: public class CategoryMap : ClassMap<Category> { public CategoryMap() { Id(x => x.ID).Column("CategoryID").Unique(); Map(x => x.Title).Column("Title").Not.Nullable(); Map(x => x.UserID).Column("UserID").Not.Nullable(); } } My Class code: public class Category { public virtual int ID { get; private set; } public virtual string Title { get; set; } public virtual Guid UserID { get; set; } public Category() { // do nothing } } And the page where I save the object: public void Add(Category catToAdd) { using (ISession session = SessionProvider.GetSession()) { using (ITransaction Transaction = session.BeginTransaction()) { session.Save(catToAdd); Transaction.Commit(); } } } I receive the error Invalid object name 'Category'. Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code. Exception Details: System.Data.SqlClient.SqlException: Invalid object name 'Category'. I think it might be that I haven't told the CategoryMap class to use the "sv_Categories" table, but I'm not sure how to do that. Any help would be appreciated. Thanks!

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