sql selectL rows to colums without subquery
I have a table in Oracle 10g that contains some information as follows:
SQL> select * from t_test;
INFO CODIGO GRUPO
---------- ---------- ----------
101 190 VTOS
100 130 VTOS
102 140 VTOS
I'd like to extract all the rows that have GRUPO='VTOS' and transpose those rows to columns. The values in CODIGO are predetermined(I know which values can be stored in that column), so would like to get something like this:
INFO_190 INFO_130 INFO_140
-------- -------- --------
101 100 102
I know I can do it with some subqueries, for example:
SELECT (SELECT info
FROM t_test
WHERE codigo = 190 AND grupo = 'VTOS') info_190,
(开发者_JS百科SELECT info
FROM t_test
WHERE codigo = 130 AND grupo = 'VTOS') info_130,
(SELECT info
FROM t_test
WHERE codigo = 140 AND grupo = 'VTOS') info_140
FROM DUAL
but I'd like to find a more efficient way. Can anyone suggest how to do it?
Assuming you have a relatively small number of codigo values, something like the following should work:
select max(decode(codigo, 190, info, '')) info_190,
max(decode(codigo, 130, info, '')) info_130,
max(decode(codigo, 140, info, '')) info_140
from t_test
where grupo = 'VTOS';
If you have multiple grupo values, group by grupo and include it in your select clause.
try this..
select case CODIGO when 190 then INFO end AS INFO_190,
case CODIGO when 130 then INFO end AS INFO_130,
case CODIGO when 140 then INFO end AS INFO_140
from t_test where grupo = 'VTOS'
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