Re: Trigger syntax - stop duplicates

[Phillip Ward]

An insert creates one or more rows.

A select returns any number of rows.

Concentrate on getting the select to return the data that you want, then leave the the insert to work with those rows.

Your select has no 'where' clause and so will return every row that matches based only on the join criteria you've specified. your insert will dutifully insert all of them, because that's what it does.

Regards, Phill W.