That should do it! Imagine a scenario where someone was updating records in the employees table and made a mistake! The employees table now looks like this:. How do we fix this? When you update multiple rows, it usually involves a lot of manual work. This query is designed to cut down on that repetitive work:. It uses the clustered index update and clustered index scan as highlighted. The subquery works efficiently, but it has its own limitations, as highlighted earlier.
The overall performance of your database depends on the table data, the number of updates, table relationships, indexes , and statistics. SQL Server execution plans are a gateway for query optimizer and query executions.
Learn how to read, interpret and analyze execution plan data. Here are three key areas to focus your SQL Server performance tuning efforts to keep your database in peak condition. You may withdraw your consent at any time. Please visit our Privacy Statement for additional information. Tweet Share Share. Set the column to its default value which will be NULL if no specific default expression has been assigned to it.
A list of table expressions, allowing columns from other tables to appear in the WHERE condition and the update expressions. An expression that returns a value of type boolean. Only rows for which this expression returns true will be updated. The row to be updated is the one most recently fetched from this cursor.
The expression can use any column names of the table or table s listed in FROM. The count is the number of rows updated. If count is 0, no rows matched the condition this is not considered an error. When using FROM you should ensure that the join produces at most one output row for each row to be modified. Create a free Team What is Teams? Collectives on Stack Overflow. Learn more. Asked today. Active today. Viewed 41 times.
Improve this question. Subhan Raj.
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