mySQL 2 mal auf selbe Tabelle zugreifen

[jak]

Die Lösung die ich verwendet habe sind zwei SELECTs die mit UNION zusammen gefasst werden. Das ist allerdings eher mühsam, da die WHERE statements für beide SELECTs angepasst werden müssen.

Von http://dev.mysql.com/doc/refman/4.1/en/union.html

Posted by Kim Mihaly on October 4 2006 5:35am

For an app I was writing I needed to list both parent & child for a 2 level tree - the first half of the union returns all the parents , the second all the children for these parents - as I was using the pear html_pager I also added a limit clause....

select parent.categoryid, parent.categoryname, parent.sequence as seq, parent.categoryid as id, '' as name, 0 as seq1
from category as parent
where parent.isasubcategoryof = 0
union
select parent.categoryid, parent.categoryname, parent.sequence as seq, child.categoryid as id, child.categoryname as name, child.sequence as seq1
from category as parent, category as child
where (child.isasubcategoryof = parent.categoryid)
order by seq, seq1

jak