encountered a SQL problem, the method to delete the duplicate phone number of id, found on the Internet is as follows.
then I tried to delete the p1 of delete p1, and SQL is invalid. The deletion statement has always been in the way of delete from table, so this is very strange, and I don"t know, can any of the great gods talk about it?
DELETE p1 from person p1 person p2 where p1.tel=p2.tel and p1.id > p2.id;
Delete the record of the same table. P1 and p2 each represent a record. If the tel of p1 is equal to the tel of p2 and the id of p1 is larger than the id of p2, delete the record of p1
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