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Subject:
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Calculate de max value of two columns
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Posted By:
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cdias
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Post Date:
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11/26/2003 2:15:17 PM
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How can I calculate the max value of two columns with a single query.
Suppose I have a table with the following information:
id col1 col2
-- ---- ----
1 10 20
2 20 30
3 12 23
The query should return the following data:
id max_value
-- ----------
1 20
2 30
3 23
Thanks in advance,
Carlos Dias
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Reply By:
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azizmasih
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Reply Date:
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11/26/2003 2:23:50 PM
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Hi Carlos,
How about the following ?
--------------------------------------------
SQL> select * from t;
ID COL1 COL2
---------- ---------- ----------
1 10 20
2 20 30
3 12 23
SQL> select id, max(col) from (
2 select id, col1 as col from t
3 union
4 select id, col2 as col from t
5 )
6 group by id;
ID MAX(COL)
---------- ----------
1 20
2 30
3 23
SQL>
--------------------------------------------
Cheers,
Prat
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