A typesafe enum of SQL string fragments. Used by Criteria and SqlExpression
to build queries. Criteria also makes most of the constants available
in order to specify a criterion.
author: author: Thomas Fischer version: $Id: SqlEnum.java 473821 2006-11-11 22:37:25Z tv $ since: 3.0
returns whether o is the same SqlEnum as this object.
Two SqlEnums are considered equal if they contain the same String.
Parameters: o - the object to compare the SqlEnum with.