For a table with transaction time, the INSERT statement cannot specify a value for the transaction-time column. The system maintains the transaction time. If the INSERT statement uses a positional assignment list, the transaction-time column position is skipped when mapping the values to the columns.
The Period value specified for the valid-time column must be assignable to the valid-time column of the target table; otherwise, an appropriate Period data type error is reported.
The SELECT statement of a nonsequenced INSERT … SELECT is executed as a nonsequenced SELECT. The result rows of the SELECT are inserted into the target table with the period of validity set to the corresponding Period value in the selected list.
If the valid-time column is not specified in the positional assignment list or in the named list and no default value is specified for the valid-time column, it defaults to NULL. A NULL in a valid-time column can be modified only by using a nonsequenced update because a current or sequenced update can never qualify this row.