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This is truly an amazing feature to add to SQL Server 2014. I use table variables all the time and this was the only thing I didn’t like about them. Up to this point, SQL Server did not support having non-clustered indexes on table variables (the one with the name that starts with the @). If you wanted to do this, you had to create/use a temp table (the one with the name that starts with #).

With SQL Server 2014, they changed this and now allow the table variables to have non-clustered indexes as well. To do this, we simply add a little bit of extra code after the column declaration.

DECLARE	@AnimalTableVar	TABLE
( AnimalID		INT,
  AnimalName	VARCHAR(50)	INDEX IX_AnimalTempTable_AnimalName
)

In the sample above, we create a table variable called @AnimalTableVar. Then when we declare the column AnimalName, we add an index called IX_AnimalTempTable_AnimalName.

Here is how selecting from this table shows up in the execution plan!
Non-Clustered Indexes For Table Variables

Reference: http://msdn.microsoft.com/en-us/library/ms188927(v=sql.120).aspx

The OUTPUT clause is an amazing part of SQL Server that many people do not know about. As corny as it is, I still remember the day that I found it. I had been searching for the whole day trying to figure out how to get the identity values from a large amount of data that I just inserted in to the database. There had to be a way… right? After searching and searching, I gave up and just accepted that it is not possible… a few days later I found exactly what I was looking for… the OUTPUT clause.

The OUTPUT clause is a part of the query that will return data from before or after the operations is completed. Let’s say that you inserted data in to a table and you wanted the ID column values (which are auto-numbers). The OUTPUT clause gives you this information! It can work on INSERT, DELETE, UPDATE, and MERGE statements. I will take you through examples of each.

To access the data that is being altered in your sql statement, you need to use special column prefixes that SQL Server makes available to you. The two special prefixes are “inserted” and “deleted”. During an insert statement, the inserted prefix is available for you to use. During a delete statement, the deleted prefix is available to you. During the update and merge statements, both the deleted and inserted prefixes are available to you. In these cases, the deleted represents the data before it was changed and the inserted represents the data after it was changed.

One thing to note is that the data being outputted must go in to a table or table variable.

OUTPUT Clause On An INSERT Statement

DECLARE	@OutputData	TABLE
		(AnimalID	INT,
		 AnimalName	VARCHAR(50))

-- Insert into the table and stick the resulting animal
--   name and identity column in to a temp variable
INSERT
INTO	Animal
		(AnimalName)
OUTPUT	inserted.AnimalID, inserted.AnimalName
INTO	@OutputData
		(AnimalID, AnimalName)
VALUES	('Pig'),
		('Dog'),
		('Chinchilla')

-- View the inserted data
SELECT	*
FROM	@OutputData

OUTPUT Clause On A DELETE Statement

DECLARE	@OutputData	TABLE
		(AnimalID	INT,
		 AnimalName	VARCHAR(50))

DELETE
FROM	Animal
OUTPUT	deleted.AnimalID, deleted.AnimalName
INTO	@OutputData
		(AnimalID, AnimalName)
WHERE	AnimalName = 'Pig'

-- View the deleted data
SELECT	*
FROM	@OutputData

OUTPUT Clause On An UPDATE Statement

DECLARE	@OutputData	TABLE
		(AnimalID	INT,
		 OldAnimalName	VARCHAR(50) ,
		 NewAnimalName	VARCHAR(50))

-- Update the table and output the animal name
--   and identity column to the temp table
UPDATE	Animal
SET	AnimalName = 'Swine'
OUTPUT	inserted.AnimalID, deleted.AnimalName, inserted.AnimalName
INTO	@OutputData
		(AnimalID, OldAnimalName, NewAnimalName)
WHERE	AnimalName = 'Pig'

-- View the updated data
SELECT	*
FROM	@OutputData

OUTPUT Clause On A MERGE Statement

DECLARE	@OutputData	TABLE
		(AnimalID	INT,
		 OldAnimalName	VARCHAR(50),
		 NewAnimalName	VARCHAR(50))

DECLARE	@ChangeData	TABLE
		(OldAnimalName	VARCHAR(50),
		 NewAnimalName	VARCHAR(50))

INSERT
INTO	@ChangeData
VALUES	('Pig', 'Swine')

-- Update the table and output the animal name
--   and identity column to the temp table
MERGE	Animal AS target
USING	@ChangeData AS source
		ON (source.OldAnimalName = target.AnimalName)
WHEN	MATCHED
THEN	UPDATE
		SET target.AnimalName = source.NewAnimalName
OUTPUT	inserted.AnimalID, deleted.AnimalName, inserted.AnimalName
INTO	@OutputData
		(AnimalID, OldAnimalName, NewAnimalName);

-- View the updated data
SELECT	*
FROM	@OutputData

Reference: http://msdn.microsoft.com/en-us/library/ms177564.aspx

SQL Server 2014 Feature – Non-Clustered Indexes For Table Variables

How To Use The OUTPUT Clause