empty check in sql code example
Example 1: sql not null
SELECT column_name FROM table_name
WHERE column_name IS NOT NULL;
Example 2: sql check for null and empty string
IF ISNULL(@param) OR @param = '' THEN doSomething...
Example 3: sql if empty then
SELECT COALESCE(NULLIF(SomeColumn,''), ReplacementColumn)
FROM SomeTable
Example 4: 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;