I always use MERGE now rather than several IF blocks (unless I'm stuck with SQL2005 and earlier). It's important to test the merge before using it on live data though! I have a template I use with a hot-key to drop the basic structure into a new procedure. If you are new to MERGE you may not know that the DELETE/INSERT/UPDATE statements can be in different orders and each statement will accept any additional logic you want to apply.

You can do all sorts of things like:

;MERGE INTO dbo.[TargetTable] AS [Target]

USING (SELECT ID AS TargetTableID FROM dbo.[BookTable]) AS [Source]

ON [Target].TargetTableID = [Source].TargetTableID

WHEN MATCHED AND [Target].isDelete = 1

THEN DELETE

WHEN MATCHED AND NULLIF([Source].Title,'') IS NOT NULL

THEN UPDATE

SET

[Target].Title = [Source].Title

,[Target].Text = [Source].Text

WHEN NOT MATCHED BY TARGET AND NULLIF([Source].Title,'') IS NOT NULL

THEN INSERT

(

Title

,Text

)

VALUES

(

[Source].Title

,[Source].Text

)

WHEN NOT MATCHED BY SOURCE AND YEAR([Target].DatePublished) < 2013

THEN DELETE;