If you use target update override, you must manually put all database reserved words in quotes.

You cannot override the default UPDATE statement if the target column name contains any of the following characters:

You can use parameters and variables in the target update query. Use any parameter or variable type that you can define in the parameter file. You can enter a parameter or variable within the UPDATE statement, or you can use a parameter or variable as the update query. For example, you can enter a session parameter, $ParamMyOverride, as the update query, and set $ParamMyOverride to the UPDATE statement in a parameter file.

When you save a mapping, the Designer verifies that you have referenced valid port names. It does not validate the SQL.

If you update an individual row in the target table more than once, the database only has data from the last update. If the mapping does not define an order for the result data, different runs of the mapping on identical input data may result in different data in the target table.

A WHERE clause that does not contain any column references updates all rows in the target table, or no rows in the target table, depending on the WHERE clause and the data from the mapping. For example, the following query sets the EMP_NAME to “MIKE SMITH” for

all

rows in the target table if any row of the transformation has EMP_ID > 100:

If the WHERE clause contains no port references, the mapping updates the same set of rows for each row of the mapping. For example, the following query updates all employees with EMP_ID > 100 to have the EMP_NAME from the last row in the mapping:

If the mapping includes an Update Strategy or Custom transformation, the Target Update statement only affects records marked for update.

If you use the Target Update option, configure the session to mark all source records as update.