Обсуждение: 3 SELECTs rolled into 1 ?
I have 3 similar SELECTs. I am wondering whether they could be rolled into one? SELECTitem.id department.id || section.id || category.id as x FROM itemLEFT JOIN product ON ...LEFT JOIN department ON ...LEFT JOIN section ON ...LEFT JOIN category ON ... SELECTitem.id department.id || section.id as x FROM itemLEFT JOIN product ON ...LEFT JOIN department ON ...LEFT JOIN section ON ... SELECTitem.id department.id as x FROM itemLEFT JOIN product ON ...LEFT JOIN department ON ... -- Best Regards, Tarlika Elisabeth Schmitz A: Because it breaks the logical sequence of discussion Q: Why is top posting bad?
am Wed, dem 04.06.2008, um 8:41:29 +0100 mailte Tarlika Elisabeth Schmitz folgendes: > I have 3 similar SELECTs. I am wondering whether they could be rolled > into one? > > > SELECT > item.id > department.id || section.id || category.id as x Syntax error, missing , between the columns ;-) > FROM item > LEFT JOIN product ON ... > LEFT JOIN department ON ... > LEFT JOIN section ON ... > LEFT JOIN category ON ... > > SELECT > item.id > department.id || section.id as x > FROM item > LEFT JOIN product ON ... > LEFT JOIN department ON ... > LEFT JOIN section ON ... > > SELECT > item.id > department.id as x > FROM item > LEFT JOIN product ON ... > LEFT JOIN department ON ... If i understand you correctly: use UNION, like select foo1 as foo, bar1 as bar from table1 UNION ALL select foo2, bar2 from table2; The result table contains 2 columns foo and bar and all rows from both selects. Andreas -- Andreas Kretschmer Kontakt: Heynitz: 035242/47150, D1: 0160/7141639 (mehr: -> Header) GnuPG-ID: 0x3FFF606C, privat 0x7F4584DA http://wwwkeys.de.pgp.net
On Wed, 4 Jun 2008 09:55:46 +0200 "A. Kretschmer" <andreas.kretschmer@schollglas.com> wrote: > am Wed, dem 04.06.2008, um 8:41:29 +0100 mailte Tarlika Elisabeth > Schmitz folgendes: > > I have 3 similar SELECTs. I am wondering whether they could be > > rolled into one? > > > > > > SELECT > > item.id, > > department.id || section.id || category.id as x > > FROM item > > LEFT JOIN product ON ... > > LEFT JOIN department ON ... > > LEFT JOIN section ON ... > > LEFT JOIN category ON ... > > > > ... > > > > SELECT > > item.id, > > department.id as x > > FROM item > > LEFT JOIN product ON ... > > LEFT JOIN department ON ... > > > If i understand you correctly: use UNION, like > > select foo1 as foo, bar1 as bar from table1 UNION ALL select foo2, > bar2 from table2; > > The result table contains 2 columns foo and bar and all rows from both > selects. Many thanks! Yes, this produces the desired result. It is more or less just a concatenation of virtually identical SELECTs with the same long WHERE clause. I had hoped to be able to express it with a single SELECT. ;-) -- Best Regards, Tarlika Elisabeth Schmitz A: Because it breaks the logical sequence of discussion Q: Why is top posting bad?