MS SQL: Custom Date and Time functions

Transact-SQL really lack a the neccessary support for creating and modifying dates and times. Now and then I have the need for creating custom dates based on year, month and day. This is not an easy task. To simplify the manipulation of dates and times a small toolkit of userdefined functions has been developed:


Date and Time functions

• Create a date from year, month and day
• Create a DateTime value from year, month, day, hours, minutes and seconds
• Create a time structure for a given date
• Extract the date portion of a DateTime value
• Extract the time portion of a DateTime value

Calendar functions

• Get the Day of Week for a given date
• Get the First Day of Week