sql - MySQL SubQuery doesn't seem to work -


i have database table named "married" consist of numerous fields, 2 fields in particular make-up table primary-key. 2 field names are; "number", "date".

there many records in duplicate share same "number" have different "dates" associated.

i need delete record (row) within each pair, "number" common between two, has older "date" associated. there goes wrong in query.

delete number married number in(select number married)  , date <any( select date married)

you want delete recent date each number. in mysql, limited in use of table deletions occurring in rest of query. fortunately, can around using join. think want:

delete m     married m join          (select number, max(date) maxd           married           group number          ) tokeep          on m.number = tokeep.number , m.date < tokeep.maxd;

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