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SUBSTRING function (ODBC compatible)


SUBSTRING ( char_expression, start_position [, length ] )


The scalar function SUBSTRING returns the substring of the character string corresponding to the first argument starting at start_position and length characters long. If the third argument, length, is not specified, the substring starting at start_position up to the end of char_expression is returned. SUBSTRING is identical to SUBSTR and provides ODBC-compatible syntax.


SELECT name, '(', SUBSTRING (phone, 1, 3) , ')',

SUBSTRING (phone, 4, 3), '-',

SUBSTRING (phone, 7, 4)

FROM customer ;


  • The first argument must be of character type.
  • The second argument must be of type INTEGER.
  • The third argument, if specified, must be of type INTEGER.
  • The values for specifying position in the character string start from one. The very first character in a string is at position one, the second character is at position two and so on.
  • The result is of character type.
  • If any of the argument expressions evaluates to null, the result is null.