Fetch or Insert into an mi_datetime variable

When a DataBlade API module uses an mi_datetime variable to fetch or insert a DATETIME value, the module must find a valid qualifier in the mi_datetime variable.

The DataBlade API takes one of the following actions, based on the value of the dt_qual field in the dtime_t structure that is associated with the variable:

When the dt_qual field contains a valid qualifier, the DataBlade API extends the column value to match the dt_qual qualifier.
Extending is the operation of adding or dropping fields of a DATETIME value to make it match a given qualifier. You can explicitly extend DATETIME values with the SQL EXTEND function and the dtextend() function.
When the dt_qual field does not contain a valid qualifier, the DataBlade API takes different actions for a fetch and an insert:
- For a fetch, the DataBlade API uses the DATETIME column value and its qualifier to initialize the mi_datetime variable.
  Zero is an invalid qualifier. Therefore, if you set the dt_qual field to zero, you can ensure that the DataBlade API uses the qualifier of the DATETIME column.
- For an insert, the DataBlade API cannot perform the insert or update operation.
  The DataBlade API sets the SQLSTATE status variable to an error-class code (and SQLCODE to a negative value) and the update or insert operation on the DATETIME column fails.