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  • NHibernate will not insert a record

    - by Brian Beckham
    I have an application that is now 4+ years old that is exhibiting some odd behavior on our latest deployment. The application uses nHibernate for all inserts / updates / selects, etc. We are currently using .NET 2.0, and nHibernate 1.2 (I know, we need to upgrade) This deployment is on Windows 2008 Server x64, IIS 7.5 - what I have seen so far is that the application runs, but is unable to insert or update records in the DB - reads seem fine so far, but writes are a problem. SOME writes actually work, inserts into some small tables, but most never even make it to the DB. Using SQL Profiler, the insert / updates never make it to the server, and turning log4net up to DEBUG, and show_sql true - the select statements appear, but the insert / update statements never make it into the log at all, and never show up at the server. What's even more odd is that the application seems to be oblivious to this - the commandandclose runs without exception (open session in view with an httpmodule), the domain objects come back with uuid's generated, etc. but never get persisted. Certainly an upgrade is due, but I would hate to try it during a deployment, and without time to accurately test the app. Any ideas?

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  • Should I use DATE and TIME as fields rather than DATETIME

    - by whitstone86
    I have a project on going for a TV guide, called mytvguide in the database - I use PHPMyAdmin. This is the structure for one table, which is called tvshow1: Field Type channel varchar(255) date date No airdate time No expiration time No episode varchar(255) setreminder varchar(255) but am not sure how to get DATE, TIME to work with the pagination script (below is the script, which works for the version with DATETIME): http://pastebin.com/6S1ejAFJ However, although the DATETIME one works - it shows programmes that air on the day itself like this: Programme 1 showing on Channel 1 2:35pm "Episode 2" Set Reminder Programme 1 showing on Channel 1 May 26th - 12:50pm "Episode 3" Set Reminder Programme 1 showing on Channel 1 May 26th - 5:55pm "Episode 3" Set Reminder but I'm not quite sure how to replicate that for the fields that use DATE, TIME functions as seen above. Any advice on this is appreciated, thanks!

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  • SQL query INSERT not working inserting values into my DB.

    - by Aiden Ryan
    Hello, I'm trying to insert registration data into a database but my php code isn't inserting the values into the DB although I'm not getting any errors either, can someone help me? this is the code i'm currently using: $connect = mysql_connect("localhost","myusername","mypassword"); mysql_select_db("application"); $queryreg = mysql_query('INSERT INTO users("username","password","email","date") VALUES("$username","$password","$email","$date")'); die ("You Have Been Registered."); I just need to add the username password email and date into the fields i have specified but it won't work, please someone help!

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  • I need to convert the result of a stored procedure in a dbml file to IQueryable to view a list in an

    - by RJ
    I have a MVC project that has a Linq to SQL dbml class. It is a table called Clients that houses client information. I can easily get the information to display in a View using the code I followed in Nerd Dinner but I have added a stored procedure to the dbml and it's result set is of IQueryable, not IQueryable. I need to convert IQueryable to IQueryable so I can display it in the same View. The reason for the sproc is so I can pass a search string tothe sproc and return the same information as a full list but filtered on the search. I know I can use Linq to filter the whole list but I don't want the whole list so I am using the sproc. Here is the code in my ClientRepository with a comment where I need to convert. What code goes in the commented spot. public IQueryable<Client> SelectClientsBySearch(String search) { IQueryable<SelectClientsBySearchResult> spClientList = (from p in db.SelectClientsBySearch(search) select p).AsQueryable(); //what is the code to convert IQueryable<SelectClientsBySearchResult> to IQueryable<Client> return clientList; }

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  • DBD::CSV: Problem with userdefined functions

    - by sid_com
    From the SQL::Statement::Functions documentation: Creating User-Defined Functions ... More complex functions can make use of a number of arguments always passed to functions automatically. Functions always receive these values in @_: sub FOO { my( $self, $sth, $rowhash, @params ); } #!/usr/bin/env perl use 5.012; use warnings; use strict; use DBI; my $dbh = DBI->connect( "DBI:CSV:", undef, undef, { RaiseError => 1, } ); my $table = 'wages'; my $array_ref = [ [ 'id', 'number' ], [ 0, 6900 ], [ 1, 3200 ], [ 2, 1800 ], ]; $dbh->do( "CREATE TEMP TABLE $table AS import( ? )", {}, $array_ref ); sub routine { my $self = shift; my $sth = shift; my $rowhash = shift; # return $_[0] / 30; }; $dbh->do( "CREATE FUNCTION routine" ); my $sth = $dbh->prepare( "SELECT id, routine( number ) AS result FROM $table" ); $sth->execute(); $sth->dump_results(); When I try this I get an error-message: DBD::CSV::st execute failed: Use of uninitialized value $_[0] in division (/) at ./so.pl line 27. [for Statement "SELECT id, routine( number ) AS result FROM "wages""] at ./so.pl line 34. When I comment out the third argument I works as expected ( because it looks as if the third argument is missing ): #!/usr/bin/env perl ... sub routine { my $self = shift; my $sth = shift; #my $rowhash = shift; return $_[0] / 30; }; ... 0, 230 1, 106.667 2, 60 3 rows Is this a bug?

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  • Faster Insertion of Records into a Table with SQLAlchemy

    - by Kyle Brandt
    I am parsing a log and inserting it into either MySQL or SQLite using SQLAlchemy and Python. Right now I open a connection to the DB, and as I loop over each line, I insert it after it is parsed (This is just one big table right now, not very experienced with SQL). I then close the connection when the loop is done. The summarized code is: log_table = schema.Table('log_table', metadata, schema.Column('id', types.Integer, primary_key=True), schema.Column('time', types.DateTime), schema.Column('ip', types.String(length=15)) .... engine = create_engine(...) metadata.bind = engine connection = engine.connect() .... for line in file_to_parse: m = line_regex.match(line) if m: fields = m.groupdict() pythonified = pythoninfy_log(fields) #Turn them into ints, datatimes, etc if use_sql: ins = log_table.insert(values=pythonified) connection.execute(ins) parsed += 1 My two questions are: Is there a way to speed up the inserts within this basic framework? Maybe have a Queue of inserts and some insertion threads, some sort of bulk inserts, etc? When I used MySQL, for about ~1.2 million records the insert time was 15 minutes. With SQLite, the insert time was a little over an hour. Does that time difference between the db engines seem about right, or does it mean I am doing something very wrong?

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  • Viewing recently edited etherpads (note new 'etherpad' tag for open sourced etherpad code!)

    - by dreeves
    Prescript: The amazing etherpad was recently open sourced. Get it here: http://code.google.com/p/etherpad. This is the first question that I know of on StackOverflow about the etherpad code. If you're part of the etherpad open source community, you might want to subscribe to the RSS feed for questions tagged 'etherpad' just in case this catches on! My actual question, which assumes you have etherpad installed on your own server: First, here's a query to view recently edited pads: SELECT id,lastWriteTime,creationTime,headRev FROM PAD_SQLMETA ORDER BY lastWriteTime, headRev; Or, if you want to run it from a unix prompt: mysql -u root -pPASSWD etherpad -e "select id,lastWriteTime,creationTime,headRev from PAD_SQLMETA order by lastWriteTime, headRev" That's handy, however lastWriteTime actually gets updated every time someone so much as views a pad in their browser. I'd rather sort the pads by when they were actually last edited. There's probably a fancy SQL query involving a join with another table that would show actual last edit time. Does anyone know what that is? Alternatively, you could have a script that notices when headRev changes but that doesn't seem like the cleanest way to do it.

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  • CREATE VIEW called multiple times not creating all views

    - by theninepoundhammer
    Noticing strange behavior in SQL 2005, both Express and Enterprise Edition: In my code I need to loop through a series of values (about five in a row), and for each value, I need to insert the value into a table and dynamically create a new view using that value as part of the where clause and the name of the view. The code runs pretty quickly, but what I'm noticing is that all the values are inserted into the table correctly but only the LAST view is being created. Every time. For example, if the values I'm using are X1, X2, X3, X4, and X5, I'll run the process, open up Mgmt Studio, and see five rows in the table with the correct five values, but only one view named MyView_x5 that has the correct WHERE clause. At first, I had this loop in an SSIS package as part of a larger data flow. When I started noticing this behavior, I created a stored proc that would create the CREATE VIEW statement dynamically after the insert and called EXECUTE to create the view. Same result. Finally, I created some C# code using the Enterprise Library DAAB, and did the insert and CREATE VIEW statements from my DLL. Same result every time. Most recently, I turned on Profiler while running against the Enterprise Edition and was able to verify that the Batch Started and Batch Completed events were being fired off for each instance of the view. However, like I said, only the last view is actually being created. Does anyone have any idea why this might be happening? Or any suggestions about what else to check or profile? I've profiled for error messages, exceptions, etc. but don't see any in my trace file. My express edition is 9.00.1399.06. Not sure about the Enterprise edition but think it is SP2.

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  • PHP/json My field names are being truncated to 30 characters. Can I stop this?

    - by Biff MaGriff
    Hi Everyone! Ok so I got this piece of vendor software that they said should be run on an apache php server and MySql database. I didn't have either of those so I put it on a PHP IIS server and I converted the code to work on SQL server. ex. mysql_select_db - mssql_select_db (among other things) So I have the following code in a php file $query = "SELECT * FROM TableName WHERE KEY_FIELD = '".$keyField."';"; $result = mssql_query($query); $arr = array(); while ( $obj = mssql_fetch_object($result) ) { $arr[] = $obj; } echo '{"results":'.json_encode($arr).'}'; and my results look something like this (captured with fiddler 2) {"results":[{"KEY_FIELD":"57", "My30characterlongfieldthatiscu":"GoodValue"}]} "My30characterlongfieldthatiscu" should be "My30characterlongfieldthatiscutoff" Kinda weird, no? The vendor claims that the app works perfectly on their end. I'm thinking this is some sort of IIS PHP limit, is there a way around it or can I expand it? I found this solution http://www.php.net/manual/en/ref.mssql.php#74834 but I don't understand it. Thanks!

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  • 600 tables in DDBB

    - by Michael
    Hi all, I'm a very young software architect. Now I'm working in a very large and I have to lead a group of developers to rewrite all the mortgage system of the bank. I'm looking at database tables and I realize that there is no any data model, neither documentation. The worst part is that there are about 1000 tables in dev environment, and like 600 in production. I trust more the production environment, but anyway, what can I do? I mean, I can suicide me or something, but is there any good reverse engineering tool, so at least I could get the schema definition with the relations between tables and comments extracted from the fields? Can you advice me something? Thanks in advance.

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  • How to Populate ComboBox from access db in C#

    - by Bomboe Cristian
    I have the next combobox: this.comboBoxProd.Enabled = false; this.comboBoxProd.FormattingEnabled = true; this.comboBoxProd.Items.AddRange(new object[] { "Cameras", "------------", " Digital IXUS 850 IS ", " Digital IXUS 900 Ti ", " Digital IXUS 75 -NEW- ", " Digital IXUS 70 -NEW- ", etc. I want to change it and take the values from a db. My database name is bd1.mdb and in the table Cameras it has the following fields: CamID, Cameras, Warranty, Year. I am only interested in the "Cameras" field. Thank you!

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  • Should I use "id" or "unique username"?

    - by roa3
    I am using PHP, AS3 and mysql. I have a website. A flash(as3) website. The flash website store the members' information in mysql database through php. In "members" table, i have "id" as the primary key and "username" as a unique field. Now my situation is: When flash want to display a member's profile. My questions: Should Flash pass the member "ID" or "username" to php to process the mysql query? Is there any different passing the "id" or "username"? Which one is more secure? Which one you recommend? I would like to optimize my website in terms of security and performance.

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  • Python: Time a code segment for testing performance (with timeit)

    - by Mestika
    Hi, I've a python script which works just as it should but I need to write the time for the execution. I've gooled that I should use timeit but I can't seem to get it to work. My Python script looks like this: import sys import getopt import timeit import random import os import re import ibm_db import time from string import maketrans myfile = open("results_update.txt", "a") for r in range(100): rannumber = random.randint(0, 100) update = "update TABLE set val = %i where MyCount >= '2010' and MyCount < '2012' and number = '250'" % rannumber #print rannumber conn = ibm_db.pconnect("dsn=myDB","usrname","secretPWD") for r in range(5): print "Run %s\n" % r ibm_db.execute(query_stmt) query_stmt = ibm_db.prepare(conn, update) myfile.close() ibm_db.close(conn) What I need it the time it takes the execution of the query and written to the file "results_update.txt". The purpose is to test an update statement for my database with different indexes and tuning mechanisms. Sincerely Mestika

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  • Migrating Data to MSSQL 2008

    - by Fred Clown
    I am trying to migrate data from an Informix database to MSSQL 2008. I've got quite a lot of data to move. I've been try multiple methods to get the data over, and so far SQLBulkCopy in multiple chunks seems to be the fastest that I can find. Does anyone know of a faster means of getting the data over? I'm trying to cut down on the transfer time so that on my cut-over date I don't run out of time to do the full cut-over. Thanks.

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  • IN SQL operator in R-Shiny

    - by Piyush
    I am taking multiple selection for component as per below code. selectInput("cmpnt", "Choose Component:", choices = as.character(levels(Material_Data()$CMPNT_NM)),multiple = TRUE) But I am trying to write a sql statement as given below, then its not working. Neither it is throwing any error message. When I was selecting one option at a time (without mutiple = TRUE) then it was working (since I was using "=" operator). But after using "multiple=TRUE" I need to use IN operator, which is not working. Input_Data2 <- fn$sqldf( paste0( "select * from Input_Data1 where MTRL_NBR = '$mtrl1' and CMPNT_NM in ('$cmpnt1')") ) Thanks in advance for any help on this. Thanks jdharrison! Pleasefind the detailed code: # server.R library(RODBC) library(shiny) library(sqldf) Input_Data <- readRDS("InputSource.rds") Mtrl <- factor(Input_Data$MTRL_NBR) Mtrl_List <- levels(Mtrl) shinyServer(function(input, output) { # First UI input (Service column) filter clientData output$Choose_Material <- renderUI({ if (is.null(clientData())) return("No client selected") selectInput("mtrl", "Choose Material:", choices = as.character(levels(clientData()$MTRL_NBR)), selected = input$mtrl ) }) # Second UI input (Rounds column) filter service-filtered clientData output$Choose_Component <- renderUI({ if(is.null(input$mtrl)) return() if (is.null(Material_Data())) return("No service selected") selectInput("cmpnt", "Choose Component:", choices = as.character(levels(Material_Data()$CMPNT_NM)),multiple = TRUE) }) # First data load (client data) clientData <- reactive({ # get(input$Input_Data) return(Input_Data) }) # Second data load (filter by service column) Material_Data <- reactive({ dat <- clientData() if (is.null(dat)) return(NULL) if (!is.null(input$mtrl)) # ! dat <- dat[dat$MTRL_NBR %in% input$mtrl,] dat <- droplevels(dat) return(dat) }) output$Choose_Columns <- renderUI({ if(is.null(input$mtrl)) return() if(is.null(input$cmpnt)) return() colnames <- names(Input_Data) checkboxGroupInput("columns", "Choose Columns To Display The Data:", choices = colnames, selected = colnames) }) output$text <- renderText({ print(input$cmpnt) }) output$data_table <- renderTable({ if(is.null(input$mtrl)) return() if (is.null(input$columns) || !(input$columns %in% names(Input_Data))) return() Input_Data1 <- Input_Data[, input$columns, drop = FALSE] cmpnt1 <- input$cmpnt mtrl1 <- input$mtrl Input_Data2 <- fn$sqldf( paste0( "select * from Input_Data1 where MTRL_NBR = '$mtrl1' and CMPNT_NM in ('$cmpnt1')") ) head(Input_Data2, 10) }) })

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  • Updating a composite primary key

    - by VBCSharp
    I am struggling with the philosophical discussions about whether or not to use composite primary keys on my SQL Server database. I have always used the surrogate keys in the past and I am challenging myself by leaving my comfort zone to try something different. I have read many discussion but can't come to any kind of solution yet. The struggle I am having is when I have to update a record with the composite PK. For example, the record in questions is like this: ContactID, RoleID, EffectiveDate, TerminationDT. The PK in this case is the ContactID, RoleID, and EffectiveDate. TerminationDT can be null. If in my UI, the user changes the RoleID and then I need to update the record. Using the surrogate key I can do an Update Table Set RoleID = 1 WHERE surrogateID = Z. However, using the Composite Key way, once one of the fields in the composite key changes I have no way to reference the old record to update it without now maintaining somewhere in the UI a reference to the old values. I do not bind datasources in my UI. I open a connection, get the data and store it in a bucket, then close the connection. What are everyone's opinions? Thanks.

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  • MySQL: Limit output according to associated ID

    - by Jess
    So here's my situation. I have a books table and authors table. An author can have many books... In my authors page view, the user (logged in) can click an author in a tabled row and be directed to a page displaying the author's books (collected like this URI format: viewauthorbooks.php?author_id=23), very straight forward... However, in my query, I need to display the books for the author only, and not all books stored in the books table (as i currently have!) As I am a complete novice, I used the most simple query of: SELECT * FROM tasks_tb This returns the books for me, but returns every single value (book) in the database, and not ones associated with the selected author. And when I click a different author the same books are displayed for them...I think everyone gets what I'm trying to achieve, I just don't know how to perform the query. I'm guessing that I need to start using more advanced query clauses like INNER JOIN etc. Anyone care to help me out :)

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  • Xml Conversion "Type mismatch" Error

    - by prema
    I am selecting a query in sql server 2005 SELECT 'Region' AS ELEMENT,(SELECT GeographyName,GeoID from @tmpTable FOR XML RAW, TYPE) FOR XML RAW('Root') This will give the output in xml as <Root ELEMENT="Region"> <row GeographyName="East" GeoID="2" /> <row GeographyName="West" GeoID="3" /> <row GeographyName="North" GeoID="4" /> <row GeographyName="South" GeoID="5" /> </Root> In aspx page, i want to get this function Populatedata(obj, val) { var xmlDom = new JXmlDom(obj, false); --> at this point i am getting error var nodeHeader = xmlDom.selectNodes("//row"); // my code goes here } function JXmlDom (xml,isFile) { this.load=load; this.loadXML=loadXML; this.selectNodes=selectNodes; this.text=text; this.selectSingleNode=selectSingleNode; this.documentElement=documentElement; this.transformNode=transformNode; if (isFile) { this.dom=this.load (xml); }else { this.dom=this.loadXML (xml); } function loadXML (xml) { if (window.ActiveXObject) { var dom=new ActiveXObject("Microsoft.XMLDOm"); dom.async=false; dom.loadXML (xml); } if (document.implementation && document.implementation.createDocument) { var domParser=new DOMParser(); var dom=domParser.parseFromString (xml,"text/xml"); } return dom; } But when i am calling this i am getting an error as Type mismatch.Can anyone help me

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  • Multiple Foriegn Keys from One Table linking to single Primary Key in second Table

    - by croker10
    Hi all, I have a database with three tables, a household table, an adults table and a users table. The Household table contains two foreign keys, iAdult1ID and iAdult2ID. The Users table has a iUserID primary key and the Adult table has a corresponding iUserID foreign key. One of the columns in the Users table is strUsername, an e-mail address. I am trying to write a query that will allow me to search for an e-mail address for either adult that has a relation to the household. So I have two questions, assuming that all the values are not null, how can I do this? And two, in reality, iAdult2ID can be null, is it still possible to write a query to do this? Thanks for your help. Let me know if you need any more information.

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  • How to configure an index.htm file in IIS?

    - by salvationishere
    I am running IIS 6.0 on an XP OS using VS 2008 and SQL Server 2008 (Full install). I developed two web apps. Both of these I can run from IIS by setting them to the default website. However, now I tried adding an index.htm file. Real simple; all it has is two hyperlinks to these web apps. But now only the first web app works. The first web app is pure VS. The second web app modifies an Adventureworks database table. But now when I click the hyperlink for the second web app, it gives me the error below. However this error doesn't make sense to me cause I have the two web apps configured as two virtual directories beneath C:\inetpub\ and the index.htm file is also beneath C:\inetpub. And the default website is set to home directory C:\inetpub\ with Document index.htm on top. Also, why does the first web app work and not the second now? Server Error in '/AddFileToSQL' Application. The path '/AddFileToSQL/App_GlobalResources/' maps to a directory outside this application, which is not supported. 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.Web.HttpException: The path '/AddFileToSQL/App_GlobalResources/' maps to a directory outside this application, which is not supported. Source Error: An unhandled exception was generated during the execution of the current web request. Information regarding the origin and location of the exception can be identified using the exception stack trace below.

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  • MS-Access auto enter information based on date

    - by Desert Spider
    I have a query that calculates an employees anniversary date. I would like that query to generate an entry event for my Table based on the current date. Basically automatically generate an anniversary vacation accrual when their anniversary date comes. Here is an example of my table. Table name "SchedulingLog" LogID "PrimaryKey AutoNbr" UserID "Employee specific" LogDate EventDate Category "ex Vacation, Anniversary..." CatDetail "ex. Vacation Day Used, Anniversary..." Value "ex. -1, 1..." My query Query Name "qry_YOS" UserID "Employee Specific" DOH "Employee hire date" YearsOfService "calculated Field" Annual "calculated Field" Schedule "Employee Specific" Annual Vac Days "calculated field" Anniversary "calculated Field" Query associated SQL INSERT INTO schedulinglog (userid, [value], eventdate, logdate, category, catdetail) SELECT roster.userid, [annual] * [schedule] AS [Value], Month([wm doh]) & "/" & Day([wm doh]) & "/" & Year(DATE()) AS EventDate, DATE() AS LogDate, category.[category name] AS Category, catdetail.catdetail FROM roster, tblaccrual, category INNER JOIN catdetail ON category.categoryid = catdetail.categoryid WHERE (( ( [tblaccrual] ! [years] ) < Round(( DATE() - [wm doh] ) / 365, 2) )) GROUP BY roster.userid, roster.[wm doh], Round(( DATE() - [wm doh] ) / 365, 2), roster.schedule, Month([wm doh]) & "/" & Day([wm doh]) & "/" & Year(DATE()), DATE(), category.[category name], catdetail.catdetail HAVING ( ( ( category.[category name] ) LIKE "vacation*" ) AND ( ( catdetail.catdetail ) LIKE "anniversary*" ) ); I know it is possible I just dont know where to begin.

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  • INSERT INTO ...SELECT syntax error in join operator

    - by user1477356
    I'm trying to write a shopping basket into a order + orderline in a sql database from C# asp.net. the orderline will contain a ordernumber, total price, productid, quantity etc. for every item in the basket. The order itself will contain the ordernumber as primary key and will be linked to the different lines through it. Everything worked fine yesterday, but now as i tried to use a SELECT command in the insert into statement to get things more dynamic i'm getting the above described syntax error. Does anybody know what's wrong with this statement: INSERT INTO [order] (klant_id,totaalprijs,btw,subtotaal,verzendkosten) SELECT klant.id , SUM(orderregel.totaalprijs) , SUM(orderregel.btw) , SUM(orderregel.totaalprijs) - SUM(orderregel.btw) , 7.50 FROM orderregel INNER JOIN klant ON [order].klant_id = klant.id WHERE klant.username = 'jerry' GROUP BY id; the ordernumber in the "order" table is on autonumber, in the asp codebehind there is a for each which handles the lines being written for every product, there's an index set on 0 outside of this loop and is heightened with 1 every end of it. The executenonquery of the order is only executed once at the beginning of the first loop and the lines are added after with MAX(ordernumber) as ordernumber. I hope i have provided enough information and somebody is capable of helping me. Thanks in advance!

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  • Architecture for multiple web apps and databases.

    - by Matt
    We used to have only one web app, but now we are breaking it down into multiple ones. Each one will be packaged as separate product (web app) Some have things in common some do not. It was originally coded with php and using Postgresql 8.4 and CodeIgniter as the framework. I am looking for some good suggestions on how I should set up multiple web apps. They all have their own somewhat unique data. Some data in the databases can be common to some apps but not all. All the apps will be on one server and will have some kind of API to manipulate data. I want it to be structured such that one User account can access any product they purchase. (kinda like google accounts) I do not know if its a good idea to have multiple database, or just to have one big one. eventually we will be using S3 for some videos and other images. Your thoughts and suggestions are much appreciated.

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  • Find all those columns which have only null values, in a MySQL table

    - by Robin v. G.
    The situation is as follows: I have a substantial number of tables, with each a substantial number of columns. I need to deal with this old and to-be-deprecated database for a new system, and I'm looking for a way to eliminate all columns that have - apparently - never been in use. I wanna do this by filtering out all columns that have a value on any given row, leaving me with a set of columns where the value is NULL in all rows. Of course I could manually sort every column descending, but that'd take too long as I'm dealing with loads of tables and columns. I estimate it to be 400 tables with up to 50 (!) columns per table. Is there any way I can get this information from the information_schema? EDIT: Here's an example: column_a column_b column_c column_d NULL NULL NULL 1 NULL 1 NULL 1 NULL 1 NULL NULL NULL NULL NULL NULL The output should be 'column_a' and 'column_c', for being the only columns without any filled in values.

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  • MySQL whats wrong with my foreign keys?

    - by Skiy
    Hello, what is wrong with the two foreign keys which I have marked with comments? create database db; use db; create table Flug( Flugbez varchar(20), FDatum Date, Ziel varchar(20), Flugzeit int, Entfernung int, Primary Key (Flugbez, FDatum)); create table Flugzeugtyp( Typ varchar(20), Hersteller varchar(20), SitzAnzahl int, Reisegeschw int, primary key (Typ) ); create table flugzeug( Typ varchar(20), SerienNr int, AnschDatum Date, FlugStd int, primary key(Typ,SerienNr), foreign key(Typ) references Flugzeugtyp(Typ)); create table Abflug( Flugbez varchar(20), FDatum Date, Typ varchar(20), Seriennr int, Kaptaen varchar(20), Primary key(Flugbez,FDatum,Typ,SerienNr), Foreign key(Flugbez) references Flug(Flugbez), -- Foreign key(FDatum) references Flug(FDatum), Foreign key(Typ) references Flugzeugtyp(Typ) -- ,Foreign key(SerienNr) references Flugzeug(SerienNr) ); When I uncomment these, I get: ERROR 1005 (HY000): Can't create table 'db.abflug' (errno: 150)

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