INSERTING or UPDATING automatically

i am using visual web developer 2005 and SQL Express 2005 with VB as the code behind

i have a button and in the button click event i have written codes to INSERT to a database table - it has one primary key

so when i click the button, if there is already a row with primary key fields value as 10 and if i try to INSERT with the same value in the primary key field there will occur primary key constraint

so , if i try to INSERT with the already existing primary key fields value, instead of INSERTing it should be UPDATEd without generating any error

please help me

In ur SQl procedure

Include

If exists (select [PrimaryKeyColumn] from UrTable where PrimarKey = @.PrimaryKey)

Update ...

else

Insert ...

Like this u get to check for existing key , if exists it will execute an update else an insert

Hope that helps u