sql - how to work duplicate values delete from query -
this query....
delete second_salary a.rowid > ( select b.rowid second_salary b a.salary = b.salary)
can 1 explain query?
sql 1:
delete second_salary a.rowid > (sql 2)
browse each record in table second_salary, if record have rowid > value in array result of sql 2 delete it.
sql 2:
(with a.salary number knew form record reviewed, example n)
select b.rowid second_salary b a.salary = b.salary
result return: array rowid of records have n = b.salary
end: retain record have smalless rowid in records have salary simalar.
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