"id" "parent" "name"
"1" "0" "Books"
"2" "1" "Crime Fiction"
"3" "2" "Death On the Nile"
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从上面的内容,我如何选择name父行的名称和child.这里,将提供子行的名称.我需要得到name父母的.
期望的输出:
@id = 3
Crime Fiction //This is the name of the parent row - in this case 2
Death on the Nile // This is the name of the row who's id was supplied.
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如何在同一张桌子内进行选择?
select parent.name, child.name
from your_table child
left join your_table parent on child.parent = parent.id
where child.id = 3
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