The DBC.ColumnsV[X] views provide complete information for table columns but provide only limited information for view columns. For view columns, DBC.ColumnsV[X] provides a NULL value for ColumnType, DecimalTotalDigits, DecimalFractionalDigits, CharType, ColumnLength, and other attributes related to data type.
To obtain complete information about view columns, issue a SELECT request on either DBC.ColumnsQV[X] or DBC.ColumnJQV[X]. A SELECT request on DBC.ColumnsQV[X] or DBC.ColumnsJQV[X] can also be joined with other views and tables.
- DBC.ColumnsQV[X] provides the same information as DBC.ColumnsV[X] for all database objects. DBC.ColumnsQV[X] additionally provides complete information for view columns.
- DBC.ColumnsJQV[X] provides the same information as DBC.ColumnsV[X] for tables, NoPI tables, and views, and DBC.ColumnsJQV[X] additionally provides complete information for view columns. DBC.ColumnsJQV[X] does not provide information for database objects other than tables, NoPI tables, and views. The filter improves performance for requests that return information about tables and views only.
The following request lists all the VARCHAR columns of the view 'Views_Database.Dept300':
SELECT * FROM DBC.ColumnsQV WHERE DatabaseName='Views_Database' AND TableName='Dept300' AND ColumnType = 'CV';