我正在研究
mysql資料庫.
我有一張**,這張表包含
employeeid和reportingemployeeid列
select e3.`reportingemployeeid` as level0,e2.`reportingemployeeid` as level1,e1.`reportingemployeeid` as level2,e1.`employeeid` as level3
from empreporting e1
left join empreporting e2 on e1.`reportingemployeeid` = e2.`employeeid`
left join empreporting e3 on e2.`reportingemployeeid` = e3.`employeeid`
以上查詢給出以下結果：
level0 level1 level2 level3
\n \n 379 369
\n 379 484 372
\n \n \n 379
所需的結果格式為：
level0 level1 level2 level3
379 369 \n \n
379 484 372 \n
379 \n \n \n
請任何人幫助我.
提前致謝
普拉卡什
最佳答案 最後寫的查詢
select
case
when e3.`reportingemployeeid` is not null then e3.`reportingemployeeid`+1000000
when e3.`reportingemployeeid` is null and e2.`reportingemployeeid` is not null then e2.`reportingemployeeid`
when e3.`reportingemployeeid` is null and e2.`reportingemployeeid` is null and e1.`reportingemployeeid` is not null then e1.`reportingemployeeid`
when e3.`reportingemployeeid` is null and e2.`reportingemployeeid` is null and e1.`reportingemployeeid` is null and e1.`employeeid` is not null then e1.`employeeid`
end as level0,
case
when e3.`reportingemployeeid` is not null then e2.`reportingemployeeid`
when e3.`reportingemployeeid` is null and e2.`reportingemployeeid` is not null then e1.`reportingemployeeid`
when e3.`reportingemployeeid` is null and e2.`reportingemployeeid` is null and e1.`reportingemployeeid` is not null then e1.`employeeid`
when e3.`reportingemployeeid` is null and e2.`reportingemployeeid` is null and e1.`reportingemployeeid` is null and e1.`employeeid` is not null then null
end as level1,
case
when e3.`reportingemployeeid` is not null then e1.`reportingemployeeid`
when e3.`reportingemployeeid` is null and e2.`reportingemployeeid` is not null then e1.`employeeid`
when e3.`reportingemployeeid` is null and e2.`reportingemployeeid` is null and e1.`reportingemployeeid` is not null then null
when e3.`reportingemployeeid` is null and e2.`reportingemployeeid` is null and e1.`reportingemployeeid` is null and e1.`employeeid` is not null then null
end as level2,
case
when e3.`reportingemployeeid` is not null then e1.`employeeid`
when e3.`reportingemployeeid` is null and e2.`reportingemployeeid` is not null then null
when e3.`reportingemployeeid` is null and e2.`reportingemployeeid` is null and e1.`reportingemployeeid` is not null then null
when e3.`reportingemployeeid` is null and e2.`reportingemployeeid` is null and e1.`reportingemployeeid` is null and e1.`employeeid` is not null then null
end as level3
from empreporting e1
left join empreporting e2 on e1.`reportingemployeeid` = e2.`employeeid`
left join empreporting e3 on e2.`reportingemployeeid` = e3.`employeeid`
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