SQL Date Functions

SQL date functions allow you to manipulate date and time effectively. You can use the date functions for various operations such as adding days to a date, calculating the difference between two dates, or extracting a part of a date.

Section 1. Getting the Current Date & Time Functions #

This section shows you how to get the current date, time, and timestamp value using various date and time retrieval functions.

  • CURRENT_DATE – Returns a date value that represents the current date.
  • CURRENT_TIME – Returns the time value that represents the current time.
  • CURRENT_TIMESTAMP – Returns a timestamp that represents the current date and time.

Section 2. Extracting Date & Time Components #

This section shows you how to use the EXTRACT and DATEPART functions to extract a specific component such as year, month, day, hour, minute, and second from a date, time, or timestamp value.

Section 3. Arithmetic Functions #

This section introduces the functions that perform date arithmetic operations, including adding and subtracting.

  • DATEADD – Adds an interval to a date/time value.
  • DATEDIFF – Returns the difference between two dates or times.
  • DATE_TRUNC – Truncates a date/time value to a specified precision such as year, month, day, hour, minute, and second.

Section 4. Date and Time Conversion Functions #

This section shows you how to convert between a date and time and non-datetime values.