mysql - SQL - Left outer join with 2 tables and derived tables -

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my scenario follows:

table persons   - id (primary key)   - name    table logs   - id (primary key)   - person_id (foreign key)   - datetime   - status

now want create sql query in order retrieve:

  • all names persons without relation table logs
  • and relation table logs linked field id , person_id.
  • only latest records person table logs (ie latest log id)

this query retrieves names matched relation:

select p.id, p.name, date_format(l.datetime,'%d-%m-%y %h:%i:%s') datetime, l.status          persons p left outer join logs l          on p.id = l.person_id         l.id in (select id logs t1              inner join (select max(id) max_id logs              group person_id             ) t2             on t1.id = t2.max_id)         order l.status, p.name";

how names without relation table logs well?

you can use left join:

select p.name  persons p  left join logs l on p.id = l.person_id l.id null

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