System Functions

This page provides you with the commonly used system functions in SQL Server that return objects, values, and settings in SQL Server:

  • CAST – cast a value of one type to another.

  • CONVERT – convert a value of one type to another.

  • CHOOSE – return one of the two values based on the result of the first argument.

  • ISNULL – replace NULL with a specified value.

  • ISNUMERIC – check if an expression is a valid numeric type.

  • IIF – add if-else logic to a query.

  • TRY_CAST – cast a value of one type to another and return NULL if the cast fails.

  • TRY_CONVERT – convert a value of one type to another and return the value to be translated into the specified type. It returns NULL if the cast fails.

  • TRY_PARSE – convert a string to a date/time or a number and return NULL if the conversion fails.

  • Convert datetime to string – show you how to convert a datetime value to a string in a specified format.

  • Convert string to datetime – describe how to convert a string to a datetime value.

  • Convert datetime to date – convert a datetime to a date.