Updating Relational SQL Tables

Updating a table with data from another table in the same database is something I find myself doing pretty frequently – I use this example quite a bit so I thought I’d post it for easy reference. It facilitates the updating of one table with data from another table, using a key relationship:

Take for example TableA with the following columns…

ModelId (PK)

CarName

VehicleDescription

CarSerialId

And TableB with the following columns…

MaintenanceId (PK)

ModelId (FK)

MaintenanceHist

OwnerName

CarDescription

If I wanted to update the CarDescription column in TableB with the data in the VehicleDescription column in Table A, joining on ModelId, this is how it would be done:

UPDATE [DatabaseName].[dbo].[TableB]

SET CarDescription = TableA.VehicleDescription

FROM TableB, TableA

WHERE TableB.ModelId = TableA.ModelId