Solutions for INSERT OR UPDATE on SQL Server

Question

Assume a table structure of MyTable(KEY, datafield1, datafield2...).

Often I want to either update an existing record, or insert a new record if it does

Answer 1

MS SQL Server 2008 introduces the MERGE statement, which I believe is part of the SQL:2003 standard. As many have shown it is not a big deal to handle one row cases, but when dealing with large datasets, one needs a cursor, with all the performance problems that come along. The MERGE statement will be much welcomed addition when dealing with large datasets.