public Class<?> getClazz() {
        return clazz;
      }
Generate the ANSI SQL92 filter for the given expression tree
@param catName catalog name
@param dbName db name
@param tableName table name
@param partitionKeys partition keys
@param params the ordered parameters for the resulting expression
@param joins the joins necessary for the resulting expression
@return the string representation of the expression tree
standalone-metastore/metastore-server/src/main/java/org/apache/hadoop/hive/metastore/MetaStoreDirectSql.java