Databases :: Delete Duplicate Records From MySQL Table?
Sep 20, 2010
I have Revision column in Quote table with time stamp (MySql table) now i am viewing the entire date and time my end user want to view only Date he doesnot want to see time how can i pull only date.i am displaying revision column in two ways one in grid view and another one in field value
Query in my Grid view
Dim query As String = "SELECT QuoteNumber,Revision,Vendor,PartNumber,status,Customer,Requestor from quotes"
On select check box in grid view, filed values will be loaded with data.
I'm trying to delete a bunch of records in mysql. The record info to delete (userid, name) is stored in an arraylist. It seems to only delete the first record and gives an error ("Transaction has already been rolled back or is not pending.") afterwards. I have the transaction commit inside the loop which I think is the issue but not sure how to go further if I bring it outside of the loop. Here's the relevant bits of the code.
try { ArrayList alist = new ArrayList(); //alist gets populated with data like (12345,robot)(23456,car) here. MySqlConnection conn2 = new MySqlConnection(query_connection); conn2.Open(); MySqlCommand command2 = conn2.CreateCommand(); MySqlTransaction mytransaction; mytransaction = conn2.BeginTransaction(); command2.Transaction = mytransaction; for (int i = 0; i < alist.Count; i++) { string[] s = alist[i].ToString().Split(','); try { command2.CommandText = "DELETE from users_settings WHERE UserID=" + s[0].ToString(); command2.ExecuteNonQuery(); command2.CommandText = "DELETE from users WHERE ID=" + s[0].ToString(); command2.ExecuteNonQuery(); mytransaction.Commit(); } catch (Exception e){ mytransaction.Rollback(); } } } catch(Exception e){ }
i have populated the gridview dynamically and set the ShowDeleteButton = true.. i have the delete command but i cant delete the specific row i wanted to delete..
protected void GridView1_RowDeleting(object sender, GridViewDeleteEventArgs e) { string ann = (GridView1.DataKeys[e.RowIndex].Values[3].ToString()); MySqlCommand update = new MySqlCommand("DELETE FROM announcement where ID = '"+ann+"'", conn);
[Code]....
how to get the values of the row that i want to delete.
I am using asp.net 2010 with mysql database. Is it practical for large amounts of data ? say 10 million records ? cuz some people said to me that using this combination, i'll be having performance issues as database grows.
i done one web application in this application i need to transfer the data from one table to another automatically when the time is 10.00PM. i need to write this function sepearte time function not in page load function.the user select any of page the data should be transfer from one to another without page load only using time control function..
Before I get too far down the road I just want some advice. I'm building a web app using VWD2008 and MySQL 5. I've got the membership provider stuff working fine and have an odbc connection setup which works "fine". what I've noticed is that when I configure a new sqldatasource (that will be used to provide data to a listview or something) the Advanced -> generate Insert,Update..... option is disabled. I'm assuming its because of the sql syntax difference of the square brackets issue between MS SQL Server and MySQL.
Before I start writing all my own insert and update statements does anyone know if there is a way to get MySQL and VWD to talk the same language, maybe a different connector or something. I'm using mysql-connector-odbc-3.51.15
now the system always prompts a error message about insert duplicate key into Sybase database.how can i prompt a message box instead of this error message when i insert duplicate key into sybase database table. any code can check what type of error then prompt different alert message.
how can i create a backup table for my MySql base table.my base table name is FAB when ever user store the data into FAB table same records should be stored into back-up table automatically.how can i acheive this.i am really thank full to you if any one provide me solution.
I have applied audit trail to my webform/table its working fine.I am able to maintain the History(action,action_date) of the MySql database table from ASP.net but I want to save user name i.e action_by too so i will have history of who changed the data and when, how can i acheive to save username in history table.i have login webform in my application. History MySql Table.
I'd like to have to two tables Countries and states and make it so that any MySql user can access them for the purpose of building databiund drop down lists. What permissions do I need to assign the tables or what's the best way to do this?
How do I remove duplicate rows from a data table based upon a two column values;I want to pass in a Data Table and a column names and get the data table back with data rows where that columns value are unique.
I have a Data Table with Duplicate Rows i want to delete the duplicates rows based upon two column values if both columns values are there then Delete the row.
Actually i need to transfer data from one table to another table in mysql with codition of Time.for example i need to transfer data at 10.00am when user login at 10.00am it must be insert into another data table.. if anybody know time control
I have been trying to create a sql statement that uses a subquery to join 2 oracle tables to create a strongly typed table adapter. For example:
Select productName, (select categoryName from categories where categories.category_id = products.category_id) as Category from Products
The ASP .Net tutorial I am working through recommends using subqueries instead of joins for the insert, update and delete commands to be automatically generated by Visual Studio 2010. When I click Finish in the table adapter wizard I get the following error (I am using MySQL version 5.1 and the MySQL Data Connector 6.3.5)
Generated SELECT statement. Error in SELECT clause: expression near 'SELECT'. Error in SELECT clause: expression near 'FROM'. Missing FROM clause. Error in SELECT clause: expression near','. Unable to parse query text.
I am trying to delete record from table with proper mapping from linq to sql.There is an error stating that Rmove method not found and are u missing an assembly reference.
AdventureWorks db = new AdventureWorks("Integrated Security=sspi"); var query = from con in db.Contact where con.LastName == "Klein" select con; foreach (Contact del in query) { db.Contact.Remove(del);//???Remove not working } db.SubmitChanges(); textBox1.Text = "Contact deleted.";
Why does a very simple script which inserts 26,000 records into a mysql database (myisam, no transactions) take 13 seconds in the php implementation, and then 35-50 seconds using mono+mysql connector? I thought asp.net was faster than php? Could the problem be the mono mysql connector is "platform independent", so the performance just stinks? or does asp.net suffer more overhead than php when it comes to executing each query? Aren't there any native linux binaries for mysql connector for mono that may be faster?
I have used ASD.NET code using SQL Database for Transaction operation successfully. By changing the Database Code to interface with MYSQL an Error occurs. If I remove the Transaction Code from within the the application, it works OK by displaying the MYSQL data (Read Only) in the layout of the application. I am using Mysql Essential-4.1.22-win32 and MYSQL Connector ODBC-3.51.2. My objective is to EDIT the MYSQL Data.
I have two tables dept and employees those table have parent and child relation ship link column is deptno i want to delte department even this departmetn contains employees i want to write storedprocedure for first delte employees and after department if i wrtie these two querys in storedprocedure will i get any problems
Begin Delete from tbl_employees where Department_Id=@Department_Id Delete from tbl_Department where Department_Id=@Department_Id RETURN END
