Changing Data by Using the WHERE Clause
The WHERE clause performs the following functions:
Specifies the rows to be updated.
Indicates the rows from the source tables that qualify to supply values for the update if a FROM clause is also specified.
If no WHERE clause is specified all rows in the table are updated.
The following example implements a name change for one of the names in the
SalesReason table. The
WHERE clause limits the rows to be updated to those that contain the name
UPDATE AdventureWorks.Sales.SalesReason SET Name = N'Unknown' WHERE Name = N'Other';