There is some strange behaviour with one of my tables in MySQL. When I
perform a query with an exact match, the result set comes back empty.
When I run it with a LIKE clause, I get some results.

Does Not Work:

mysql -u prod -h mysqlsrv ws_history_stg -e "SELECT * FROM MSG WHERE
ORDER_REF = '20061108/RAPTEST/RDL611004643' ORDER BY LOG_TIMESTAMP"

Works:

mysql -u prod -h mysqlsrv ws_history_stg -e "SELECT * FROM MSG WHERE
ORDER_REF LIKE '20061108/RAPTEST/RDL611004643%' ORDER BY LOG_TIMESTAMP"

There is certainly 1 record in MSG where MSG.ORDER_REF =
'20061108/RAPTEST/RDL611004643'

Why should MySQL not return it for the first query?