Dana.Reed@clinicaldatacare.com wrote:
>
> Is there any way to get table T3 (below) from T1 and T2 using SQL (select, view, etc)?
>
> T3 is basically all INDEX values from T1 matched to IND from T2 with the corresponding KEY/VALUE pairs transposed
fromrows to columns.
>
> -------
> |INDEX| (T1)
> -------
> | 1 |
> | 2 |
> | 3 |
> -------
>
> -----------------
> |IND|KEY| VALUE | (T2)
> -----------------
> | 1 | 1 | val_a |
> | 1 | 2 | val_b |
> | 1 | 3 | val_c |
> | 2 | 1 | val_d |
> | 2 | 2 | val_e |
> | 3 | 1 | val_f |
> | 3 | 3 | val_g |
> -----------------
>
> ----------------------------------
> |T1_INDEX|KEY1VAL|KEY2VAL|KEY3VAL| (T3)
> ----------------------------------
> | 1 | val_a | val_b | val_c |
> | 2 | val_d | val_e | |
> | 3 | val_f | | val_g |
> ----------------------------------
>
I think what you are looking for is cross tabulation,
TRANSFORM statement, but I don't know if that
is supported by PostgreSQL.
Volker Paul
