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select loan_plan_id,l_collect_plan.loan_id,l_collect_detail.collect_isfinished from l_collect_plan
left join l_collect_detail on l_collect_plan.return_times=l_collect_detail.collect_volume and l_collect_plan.loan_id=l_collect_detail.loan_id
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loan_plan_id loan_id collect_isfinished
1 1 1 ----1
3 1 1 ----2
4 1 NULL ----3
5 2 NULL ----4
6 2 NULL ----5
7 2 0 ----6
7 2 1 
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SQL code:
declare @cnt int
select @cnt=count(1) from TableTest
if(@cnt==0)
insert into TableTest values(1,'abc')
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