Recently I needed to create a patch for a project and we have references in our database for wizards. These wizards exist in each folder, but cannot have more than one at a time in each folder. Currently the table does not have a unique key so I could not use:
INSERT IGNORE
Because of this I resorted to the following:
INSERT INTO tblName (reportName, folderId)
SELECT 'Wizard', 1 FROM tblName2 WHERE NOT EXISTS
(SELECT 1 FROM tblName2 WHERE reportName='Wizard' AND folderId = 1) LIMIT 1;Hope it helps someone...
