Re: ADD COLUMN ts tsvector GENERATED too slow

Also, fwiw looking at top the CPU% and MEM% activity, looks like it does data crunching work.

> On 6 Jul 2022, at 12:48 PM, Florents Tselai <florents.tselai@gmail.com> wrote:
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>> On 6 Jul 2022, at 12:38 PM, Peter Eisentraut <peter.eisentraut@enterprisedb.com> wrote:
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>> On 06.07.22 10:42, Florents Tselai wrote:
>>> I have a beefy server (40+ worker processes , 40GB+ shared buffers) and a table holding (key text, text text,) of
around50M rows. 
>>> These are text fields extracted from 4-5 page pdfs each.
>>> I’m adding the following generated col to keep up with tsvectors
>>> ALTER TABLE docs_text ADD COLUMN ts tsvector GENERATED ALWAYS AS (to_tsvector(’simple', left(text, 1048575)))
STORED
>>> I expect this to be slow, but it’s been running for 18hrs already and I certainly hope I’ve done something wrong
andthere’s a smarter way. 
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>> Maybe it's stuck on a lock?  ALTER TABLE / ADD COLUMN requires an exclusive lock on the table.
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> Looking at pg_locks and pg_stat_activity doesn’t seem like it’s stuck behind something like ACCESS SHARE or similar.
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