Convert sql row into columns

Question

I have a table:

A    B     c
a1   1     a11
a1   2     a12
a1   3     a13
a2   1     a21
a2   2     a22
a2   3     a23

and I want to convert it to:

A     C1     C2     C3
a1    a11    a12    a13
a2    a21    a22    a23

How can I write a SQL query to achieve this... I do not want to convert my table to csv and use python and do it...

Just to clarify some. Do you want to break out the C column into multiple columns based on the values in the B column? Are you trying to replace the first table design or are you trying to write a query which will keep the first table design in place but pull the values for the second table design? — Justin C
– Justin C, Commented Aug 30, 2010 at 15:18

a1ex07 · Accepted Answer · 2010-08-30 15:23:51Z

2

SELECT A,
MAX(CASE WHEN B=1 THEN c END) AS C1,
MAX(CASE WHEN B=2 THEN c END) AS C2, // etc for B=3,4
FROM table1
GROUP BY A

answered Aug 30, 2010 at 15:23

a1ex07

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