> Great. I will look into this. I am impressed the simple NFA implementation. It would be nicer if it could be implemented without using recursion.
> By the way, I tested my patch (v10) to handle more large data set and > tried to following query with pgbench database. On my laptop it works > with 100k rows pgbench_accounts table but with beyond the number I got ~~~ I meant 10k. > OOM killer. I would like to enhance this in the next patch. > > SELECT aid, first_value(aid) OVER w, > count(*) OVER w > FROM pgbench_accounts > WINDOW w AS ( > PARTITION BY bid > ORDER BY aid > ROWS BETWEEN CURRENT ROW AND UNBOUNDED FOLLOWING > AFTER MATCH SKIP PAST LAST ROW > INITIAL > PATTERN (START UP+) > DEFINE > START AS TRUE, > UP AS aid > PREV(aid) > ); I ran this against your patch. It failed around > 60k rows. Best reagards, -- Tatsuo Ishii SRA OSS LLC English: http://www.sraoss.co.jp/index_en/ Japanese:http://www.sraoss.co.jp