Allow filtering of admin track logs on the data field in sybase

[PeteDarinzo]

When an app uses a sybase datasource, attempting to filter admin track logs on the additional data field causes an SQL exception.

The cause is that some operations performed by the field filter's criterion when creating the filtering query cannot be performed on a TEXT field in sybase.

For example, a "like" or "not like" filter will throw the following when the filter criterion attempts to convert the data field to lowercase.

com.sybase.jdbc3.jdbc.SybSQLException: Function LOWER invoked with wrong number or type of argument(s).

Experimentation shows that such a query succeeds when the TEXT field is first cast as a VARCHAR of sufficient size.