write a query to delete similar records in same table
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I think simply we can do like the following..
1. First we have to transfer all data from a table to
temporary table
create table Temp_table as select * from original_table;
2. Delete all record from Original Table....
delete original_table;
3. Now we can write a query by using INSERT and UNION
If any issue let me know....
insert into original_table (select * from temp_table
UNION select * from UNION )
Is This Answer Correct ? | 0 Yes | 3 No |
Answer / umadevi
--deletes records within table without changing table name
delete from temp t1 where rowid<(select max(rowid) from temp
t2 where t1.empno=t2.empno) order by empno;
or
--create new table n insert records.
create table t1 as select distinct * from temp;
or
(truncate table)
truncate table t1;
insert into t1 select distinct * from temp;
Is This Answer Correct ? | 1 Yes | 5 No |
Answer / swapna
One way is to rename the original table to something else,
and copy the unique records into the original table.
rename 'Table2', 'Table1'
select distinct * into Table2 from Table1
drop table1
Is This Answer Correct ? | 5 Yes | 13 No |
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