join - SQL Subquery: Filter entries that return no rows -
i'm struggling on sql-query... have 3 tables:
1) jobs
2) paper1
3) paper2
paper1
, paper2
have colum job_id
corresponding job-id referenced; job id 123 has paper1.job_id
of 123.
now want see jobs have corresponding paper1
no paper2
(thus: unfinished, since paper1 , paper2 requirements job fulfilled). attempt this, didn't work out correctly:
select id jobs (select id paper1 (job_id = jobs.id) != 0 limit 1) , (select id paper2 (job_id = jobs.id) = null limit 1)
any appreciated; thanks.
try:
select job_id paper1 job_id not in (select job_id paper2 group paper2) group job_id;
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