Sql is null

This article is tagged with: Sql is null and mysql

sql is null

Tests for empty (NULL) values.
Example: Returns users that haven’t given a contact number.
SELECT * FROM users
WHERE contact_number IS NULL;

is null sql

SELECT column_names
FROM table_name
WHERE column_name IS NULL;

how to find columns with null values in sql

declare @col varchar(255), @cmd varchar(max)
DECLARE getinfo cursor for
SELECT c.name FROM sys.tables t JOIN sys.columns c ON t.Object_ID = c.Object_ID
WHERE t.Name = 'ADDR_Address'
OPEN getinfo
FETCH NEXT FROM getinfo into @col
WHILE @@FETCH_STATUS = 0
BEGIN
SELECT @cmd = 'IF NOT EXISTS (SELECT top 1 * FROM ADDR_Address WHERE [' + @col + '] IS NOT NULL) BEGIN print ''' + @col + ''' end'
EXEC(@cmd)
FETCH NEXT FROM getinfo into @col
END
CLOSE getinfo
DEALLOCATE getinfo

sql empty select

-- NOTE: this is for SQL-Oracle specifically
-- syntax:
SELECT <testing_result>
FROM DUAL;
-- example:
SELECT 1+2, 2+3, 3+4
FROM DUAL;
-- OUTPUT: 3,5,7
</testing_result>

sql not null

SELECT column_name FROM table_name
WHERE column_name IS NOT NULL;

Select without null values sql

SELECT column_names
FROM table_name
WHERE column_name IS NOT NULL;

This article is tagged with: Sql is null and mysql