MySQL Snippets: Update Statement

This post is part of the series on MySQL Snippets.

The following MySQL snippet shows an example UPDATE statement for MySQL; I’m posting this as I have trouble remembering that the order of the MySQL statement is different to that of Microsoft SQL Server; in MySQL the SET clause comes after the JOIN clause, whereas in Microsoft SQL Server, with which I am more experienced, the order is reversed.

/*
Created by Ian Grieve of azurecurve | Ramblings of an IT Professional (http://www.azurecurve.co.uk)
This code is licensed under the Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International (CC BY-NC-SA 4.0 Int).
*/
UPDATE 
	bct_custom_fieldnotes AS cfn
INNER JOIN
	bct_custom_fields AS cf
		 ON
		 	cf.TableName = cfn.TargetTableName
SET
	cfn.TargetDBTableName = cf.DBTableName
WHERE
	cf.TableName <> cfn.TargetTableName;