Does SQL Server creates Non clustered index by default

Question

Ya, it is a duplicate of this. But I just needs a clarification on this article by Pinal Dave, which says the following:

Scenario 4: Primary Key defaults to Clustered Index with other index defaults to Non-clustered index

In this case we will create two indexes on the both the tables but we will not specify the type of the index on the columns. When we check the results we will notice that Primary Key is automatically defaulted to Clustered Index and another column as a Non-clustered index.

-- Case 4 Primary Key and Defaults
USE TempDB
GO
-- Create table
CREATE TABLE TestTable
(ID INT NOT NULL PRIMARY KEY,
Col1 INT NOT NULL UNIQUE)
GO
-- Check Indexes
SELECT OBJECT_NAME(OBJECT_ID) TableObject,
[name] IndexName,
[Type_Desc]
FROM sys.indexes
WHERE OBJECT_NAME(OBJECT_ID) = 'TestTable'
GO
-- Clean up
DROP TABLE TestTable
GO

Answer 1

The only indexes that get created automatically:

• the clustered index on your primary key (unless you specify otherwise - if you define your primary key to be nonclustered, then a nonclustered index will be created)

• a unique nonclustered index when you apply a UNIQUE CONSTRAINT to a column (or set of columns)