SQL IS NOT NULL

The SQL IS NOT NULL used to find whether the specified expression is nullable; if it is not, then TRUE will be returned. Otherwise, it returns FALSE. It is always advisable to use IS NOT look for NULL values. The syntax behind this is

SELECT Column_Names 
FROM Table
WHERE Expression IS NOT NULL

SQL IS NOT NULL Example

The following screenshot will show you the data inside the table.

Source Table data 1

In this example, we will use this to SELECT and return all the customer records from the [TenCustomers] table, whose Last Name is NOT Nullable value

SELECT [CustomerKey]
      ,[FirstName]
      ,[LastName]
      ,[EmailAddress]
      ,[YearlyIncome]
      ,[EnglishOccupation]
      ,[AddressLine1]
      ,[Phone]
  FROM [TenCustomers]
  WHERE [LastName] IS NOT NULL
IS NOT NULL Example 2

It’s another example of the IS NOT NULL function. Here, we are using the [Emp] table, and the data inside this table is

Table with Empty values 5

The following Server query returns all the employee records whose Office Phone numbers are Non-empty values.

SELECT [Id]
      ,[Name]
      ,[Education]
      ,[Occupation]
      ,[YearlyIncome]
      ,[Office Phone]
      ,[Mobile]
      ,[Home Phone]
  FROM [Emp]
  WHERE [Office Phone] IS NOT NULL
Example 3

The below code Selects all the records whose Office numbers or Mobile numbers are NOT NULL values

SELECT [Id]
      ,[Name]
      ,[Education]
      ,[Occupation]
      ,[YearlyIncome]
      ,[Office Phone]
      ,[Mobile]
      ,[Home Phone]
  FROM [Emp]
  WHERE [Office Phone] IS NOT NULL OR 
	[Mobile] IS NOT NULL
IS NOT NULL Example 4