How do I check if a SQL Server text column is empty?

Question

where datalength(mytextfield)=0

ISNULL(
case textcolum1
    WHEN '' THEN NULL
    ELSE textcolum1
END 
,textcolum2) textcolum1

Actually, you just have to use the LIKE operator.

SELECT * FROM mytable WHERE mytextfield LIKE ''

To get only empty values (and not null values):

SELECT * FROM myTable WHERE myColumn = ''

To get both null and empty values:

SELECT * FROM myTable WHERE myColumn IS NULL OR myColumn = ''

To get only null values:

SELECT * FROM myTable WHERE myColumn IS NULL

To get values other than null and empty:

SELECT * FROM myTable WHERE myColumn <> ''

And remember use LIKE phrases only when necessary because they will degrade performance compared to other types of searches.

SELECT * FROM TABLE
WHERE ISNULL(FIELD, '')=''

Use the IS NULL operator:

Select * from tb_Employee where ename is null