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Showing posts with the label RETURNING

MariaDB's RETURNING feature.

There is a new feature in the MariaDB 10 Beta which caught my eye: support for returning a result set on delete . With a 'regular' DELETE operation you only get to know the number of affected rows. To get more info or actions you have to use a trigger or a foreign key. Anoter posibility is doing a SELECT and then a DELETE and with the correct transaction isolation a transactional support this will work. With the support for the RETURNING keyword this has become easier to do and it will probably bennefit performance and save you a few roundtrips and a few lines of code. There is already support for RETURNING in PostgreSQL. And PostgreSQL has an other nifty feature for which RETURNING really helps: CTE or common table expressions or the WITH keyword. I really hope to see CTE support in MySQL or MariaDB some day. An example from RETURNING and CTE in PostgreSQL: demo=# select * from t1; id | name ----+------- 1 | test1 2 | test2 3 | test3 4 | test1 5 | test2 ...