How many Non Clustered Index can be created on a single table?

During my on of the training session, I used a term that we can multiple NON clustered Indexes, instantly one of the participants  was very specific about number and said, we can have upto 249 non clustered index in a table.

I instantly said, Your information in not upto date, and you need a course refresher and that’s the reason why you are attending my training.

YES, you can have upto 999 non clustered index from SQL Server 2008 onwards.

How many Non Clustered Index can be created on a single table??

So the correct answer is you can have upto 999 non clustered index per table from SQL Server 2008 onwards but in pervious versions this was limited to 249.

Here is an example, where we are creating 999 indexes on a single table.

use tempdb
go
CREATE TABLE IndexTest
(
     column1 int  identity
)
go 
-- Creation of Multiple indexes
DECLARE @IndexID smallint,
        @Exec nvarchar(500)
SELECT @IndexID = 1
WHILE @IndexID <= 999
BEGIN
  SELECT @Exec = 'CREATE INDEX [Test' + convert(varchar(5), @IndexID) + '] ON IndexTest (column1)'
  EXEC(@Exec)
  SELECT @IndexID = @IndexID + 1
END
go 
-- Select number of indexes on a table 
SELECT count(*)  FROM sys.indexes 
WHERE object_id = object_id('IndexTest')
go 
-- DROP TABLE 
go 

What if, we try to create another one ?

You will get an error message stating, that you have reached the maximum number of indexes allowed per table.

ERROR

Msg 1910, Level 16, State 1, Line 1

Could not create nonclustered index ‘Test1000′ because it exceeds the maximum of 999 allowed per table or view.

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