IS NULL – SQL Server Syntax Example: IS NULL – T-SQL Example
IS NULL – SQL Server Syntax Example: IS NULL – T-SQL Example
Purpose: – Illustrates the SQL Server syntax for the IS NULL.
SYNTAX:
SELECT [ ALL | DISTINCT ]
[TOP ( expression ) [PERCENT] [ WITH TIES ] ]
[ INTO new_table ]
[ FROM { table_source } [ ,…n ] ]
[ WHERE test_expression IS [ NOT ] NULL ]
[ GROUP BY ]
[ HAVING search_condition ]
[ ORDER BY order_expression [ ASC | DESC ]
PURPOSE:
IS NULL returns true or false indicating whether value is NULL.
Code Sample for IS NULL:
/* IS NULL example from http://idealprogrammer.com PURPOSE: IS NULL returns true or false depending on whether the value of the expression is null. SYNTAX: expression IS [NOT] NULL SELECT [ ALL | DISTINCT ] [TOP ( expression ) [PERCENT] [ WITH TIES ] ] column1 AS displayname1, displayname2 = column_name2, column_name3 displayname3 [ INTO new_table ] [ FROM { table_source } [ ,...n ] ] [ WHERE test_expression IS [NOT] NULL ] [ GROUP BY ] [ HAVING search_condition ] [ ORDER BY order_expression [ ASC | DESC ] ] */ CREATE TABLE people( ID int, firstname varchar (20), lastname varchar (20), statecode varchar (2), alive bit, height int ) GO INSERT INTO people (ID, firstname, lastname, statecode, alive) -- height is NULL VALUES (1, 'Paul', 'Revere', 'AL', 0) GO INSERT INTO people (ID, firstname, lastname, statecode, alive, height) VALUES (2, 'John', 'Lennon', 'NY', 0, 69) GO INSERT INTO people (ID, firstname, lastname, statecode, alive, height) VALUES (3, 'Steve', 'Martin', 'NY', 1, 75) GO INSERT INTO people (ID, firstname, lastname, statecode, alive, height) VALUES (4, 'George', 'Washington', 'VA', 0, 75) GO -- Select entire table SELECT 'Entire Table', * FROM people -- 1. Example of IS NULL SELECT 'Example #1' as Example, statecode, height FROM people WHERE height IS NULL GO -- 1. Example of IS NOT NULL SELECT 'Example #2' as Example, statecode, height FROM people WHERE height IS NOT NULL GO DROP TABLE people; GO |