Re: big un stacking query - help save me from myself

Kirk Wythers <wythe001(at)umn(dot)edu> wrote:

> Here is a simplified version of the query approach I am
> attempting.

> CREATE TABLE unstacked_table AS (
>     SELECT
>         var1,
>         var2,
>         var3,
>         MAX (
>             CASE
>             WHEN variable_name = 'unstack1' THEN
>
>             VALUE
>
>             END
>         ) AS unstack1,
>         MAX (
>             CASE
>             WHEN variable_name = 'unstack2' THEN
>
>             VALUE
>
>             END
>         ) AS unstack2,
>         MAX (
>             CASE
>             WHEN variable_name = 'unstack3' THEN
>
>             VALUE
>
>             END
>         ) AS unstack3,
>         MAX (
>             CASE
>             WHEN variable_name = 'unstack4' THEN
>
>             VALUE
>
>             END
>         ) AS unstack4
>     FROM
>         stacked_table
>     GROUP BY
>         variable1,
>         variable2,
>         variable3       
> )
> ;

This is still not making sense to me.  Is VALUE intended to be a
place-holder showing where you have a literal in the code?  If so,
what is the point of using MAX?  Could you create a sample
"stacked" table, insert about 10 rows, and show the SELECT which
would give the "unstacked" form?

--
Kevin Grittner
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