Posts Tagged ‘SQL CE’

By now as you know, in this post I am going to discuss about two SQL commands we use regularly to clear data in our tables.

Usage

  1. DELETE FROM TABLENAME
  2. TRUNCATE TABLE TABLENAME

Even though they do a similar thing, there are some differences which makes them unique commands.

 

DELETE

TRUNCATE

1. Considered as Data Mining Language (DML) statement. Considered as Data Definition Language (DDL) statement.
2. Can be used to delete all or part of data in a table. Will delete all the data in a table.
3. Will log the actions. There will be no logging on record deletion.
4. Will use more locks. Will use fewer locks.
5. Will use more resources. Will use less resources.
6. Slow. Fast.
7. Will not reset the identity seed. Will reset the identity seed to 0.
8. Can be used to delete data in tables having relationships. Cannot use in tables having relationships.
9. Can be used in tables involved in log shipping or replication. Cannot be used in tables involved in log shipping or replication.
10. Transaction can be rolled back. No rollback.
11. Table may keep the empty pages. Can be released by running, SHRINKDATABASE (Database Name). Data pages related to the table will be de allocated and returned to the system.
12. Related Triggers are fired. Triggers are not fired.

 

If you used DELETE to fully remove all the records, you can reset the identity value by running the following command.

  1. DBCC CHECKIDENT (TABLENAME, RESEED, 0)

If you do have some rows left in table, simply replace 0 with the last identity column value. For example if you put 5 instead of 0 then the next record inserted into the table will have an identity column value of 6.

If you jus need to check the current identity value just use the following command.

  1. DBCC CHECKIDENT (TABLENAME, NORESEED)

Project has Stopped Working

Posted: March 5, 2010 in SQL Server
Tags: , ,

If you create a .NET application to use SQL CE database when you try to run your application on a Windows Vista or Windows 7 machine you might get an error saying your application did stop working, and the error details might show that your are having a problem with System.Data.SQLServerCE.

The reason for this is that your system is not having the SQL Server CE runtime in your machine. To fix it what you need to do is to install the Microsoft SQL Server Compact 3.5 Service Pack 1 on your system. You can download it from the following Microsoft link.

http://www.microsoft.com/downloads/details.aspx?FamilyId=DC614AEE-7E1C-4881-9C32-3A6CE53384D9&displaylang=en