The default query contains a SELECT statement that includes all lookup fields in the mapping. The SELECT statement also contains an ORDER BY clause that orders all columns in the same order in which they appear in the Lookup transformation.

If you want to change the ORDER BY clause, add a WHERE clause, or transform the lookup data before it is cached, override the default query. For example, you might use database functions to adjust the data types or formats in the lookup table to match the data types and formats of fields that are used in the mapping. Or, you might override the default query to query multiple tables.

Override the default query on the

Advanced

tab of the Lookup transformation. Enter the entire SELECT statement in the

Lookup SQL Override

field. Use an alias for each column in the query. If you want to change the ORDER BY clause, append "

--

" to the end of the query to suppress the ORDER BY clause that the

mapping

task generates.