In the table there are more than 3 tons of records with the same content, how can you delete them in one query? Suppose if the table in one of the fields has the same text.
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1 answer
Let the main table table1 contain fields: id (int not null auto_increment primary key), data (varchar). There are duplicates in the data field. You can remove duplicates for example:
create a new table table2 (copy of table1 table):
insert into table2 (select * from table1);
remove duplicates from the main table:
delete from table1 where id is not in (select min (id) from table2 group by data);
remove table table2:
drop table table2;
And you can immediately select only unique entries in the data field from table1.
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