The result of a HELP COLUMN statement using a Unicode view differs from the results for the same column using a Compatibility view. For details, see Teradata Vantage™ - Advanced SQL Engine International Character Set Support, B035-1125.
In this example, HELP COLUMN returns information for the tablename column from the Unicode TablesV view:
HELP COLUMN dbc.tablesv.tablename; *** Help information returned. One row. Column Name TableName Type CV Nullable N Format X(128) Max Length 256 Decimal Total Digits ? Decimal Fractional Digits ? Range Low ? Range High ? UpperCase N Table/View? V Indexed? Y Unique? N Primary? S Title ? Column Constraint ? Char Type 2 IdCol Type ? ? UDT Name ? ?
The following HELP COLUMN request uses the DBC.Tables view instead of the DBC.TablesV view:
HELP COLUMN dbc.tables.tablename; *** Help information returned. One row. *************Column Name TableName Type CF Nullable Y Format X(30) Max Length 30 Decimal Total Digits ? Decimal Fractional Digits ? Range Low ? Range High ? UpperCase N Table/View? V Indexed? N Unique? ? Primary? ? Title ? Column Constraint ? Char Type 1 IdCol Type ? ? UDT Name ? ?
The differences between this result and the result using the DBC.TablesV view are highlighted in boldface. The Type, Format, Max Length, and Char Type are different because the Compatibility view casts the object name to 30 fixed characters in the Kanji1, or Latin, server character set.
Text strings work in a similar fashion. For example, the ColumnTitle column of the Columns compatibility view and the ColumnsV Unicode view returns different values for Type, Format, Max Length, and Char Type.