Am 08.02.2016 um 21:33 schrieb Vitaly Burovoy: > On 2/8/16, Johannes <jotpe@xxxxxxxxx> wrote: >> >> Am 08.02.2016 um 20:32 schrieb Vitaly Burovoy: >>> On 2/8/16, Adrian Klaver <adrian.klaver@xxxxxxxxxxx> wrote: >>>> Based on rough guess of the above, without seeing actual table schemas: >>>> >>>> select id, t0.col1, t1.col1, col2, ... from t0 JOIN t1 ON t0.id = >>>> t1.t0_id where id = (select max(id) from t0 where col1 = value1 and col2 >>>> = value2 and ...); >>> >>> I don't think it is a good solution because it leads to copying >>> columns from the t0 which is wasting net traffic and increasing >>> complexity at the client side. Moreover it works iff t0 returns only >>> one row. >> >> I had same doubts. >> CTE would be first class, if it was be reusable for other statements. >> >> Johannes > > CTEs are temporary tables for a _statement_ for using a single > statement instead of several ones (create temp table, insert into, > select from it, select from it, drop temp table). > > But it is not your case because CTEs are for a queries which return a > single set of rows. Your case is returning two sets (one row with > several columns from t0 and several rows with a single columns from > t1). Sure. Thanks for the temporary table example! Johannes
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