performance - Subquery v/s inner join in sql server

Question

I have following queries

First one using inner join

SELECT item_ID,item_Code,item_Name 
FROM [Pharmacy].[tblitemHdr] I 
    INNER JOIN  EMR.tblFavourites F ON I.item_ID=F.itemID
WHERE F.doctorID = @doctorId AND F.favType = 'I'

second one using sub query like

SELECT item_ID,item_Code,item_Name from [Pharmacy].[tblitemHdr]
WHERE item_ID IN
(SELECT itemID FROM EMR.tblFavourites
WHERE doctorID = @doctorId AND favType = 'I'
)

In this item table [Pharmacy].[tblitemHdr] Contains 15 columns and 2000 records. And [Pharmacy].[tblitemHdr] contains 5 columns and around 100 records. in this scenario which query gives me better performance?

Answer 1

Usually joins will work faster than inner queries, but in reality it will depend on the execution plan generated by SQL Server. No matter how you write your query, SQL Server will always transform it on an execution plan. If it is "smart" enough to generate the same plan from both queries, you will get the same result.

Here and here some links to help.