Max Long Varchar Size Attribute MaxLongVarcharSize (MLVS) Purpose Specifies the maximum size of columns of type SQL_LONGVARCHAR that the driver describes through result set descriptions and catalog functions. Valid Values A positive integer from 1 to x where: x is maximum size of the SQL_LONGVARCHAR data type. Default None. The actual size of the columns from the database is persisted to the application. GUI Tab Advanced