Add migration to merge dittos in stats

[Fabio1988]

closes #347

[lenisko]

Hmmm...

1. Those tables are missing in migration:

pokemon_hundo_stats
pokemon_iv_stats
pokemon_nundo_stats
pokemon_shiny_stats

2. I wouldn't create temporary table, maybe just set them temporary as pokemon_id = 65535, remove and them update? Or make a new table with more randomized name :)

[jfberry]

The rows need merging not updating; I’m not sure it can easily be done without a temp table. Can you expand on your suggestion Len?

[lenisko]

@jfberry something like that

START TRANSACTION;

UPDATE pokemon_stats SET pokemon_id = 65535 WHERE pokemon_id = 132;

INSERT INTO pokemon_stats (date, area, fence, pokemon_id, form_id, count)
SELECT
    date,
    area,
    fence,
    132 AS pokemon_id,
    0   AS form_id,
    SUM(count) AS count
FROM pokemon_stats
WHERE pokemon_id = 65535
GROUP BY date, area, fence
ON DUPLICATE KEY UPDATE
    count = count + VALUES(count);

DELETE FROM pokemon_stats WHERE pokemon_id = 65535;

COMMIT;

But yeah, just noticed its temporary table creation so it doesn't really matter. Either way we need to run it for multiple tables not single.

[jfberry]

Actually this approach might work even without moving the pokemon id since you can do form<>0

worth a go.