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select id , sum(stptime) as stptime from jl group by id
ÄãÈ·¶¨ÊÇ SQL code: select sum(stptime) as stptime from jl
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Ó¦¸Ã¸Ä³É SQL code: select j1.id,sum(stptime) as stptime from jl group by j1.id