In Informix and SQL Server, you can use the MONTH function to get the month (an integer number 1-12) of the specified datetime.
Informix:
-- Get the month SELECT MONTH(TO_DATE('2024-12-06', '%Y-%m-%d')) FROM systables WHERE tabid=1; /* 12 */
SQL Server:
-- Get the month SELECT MONTH('2024-12-06'); /* 12 */
For more information, see SQL Server to PostgreSQL Migration