On 22 March 2014 00:59, Vik Fearing <vik.fear...@dalibo.com> wrote: > On 03/22/2014 01:43 AM, Thom Brown wrote: >> Hi, >> >> I've created a table with 1000 partial indexes. Each one matches >> exactly one row based on the predicate WHERE id = <value>. >> >> However, when I perform an UPDATE of a single row in a transaction, >> I've noticed that all those partial indexes show up in pg_locks with >> RowExclusiveLock. >> >> Only 2 of those indexes have a reference to the row: the primary key >> and a single partial index. >> >> Is it necessary for a partial index that doesn't include the row to be >> involved in locking? > > What if the update puts the row into one of the other indexes?
Well here's where I'm confused. The entries in pg_locks show than a RowExclusiveLock is being held on the index for which there is no matching row. What does that translate as? There is also a RowExclusiveLock on the table itself too, which is what I expect to see. Also, a delete results in all the locks being taken too. That can't possibly result in a new entry being put into any of those indexes. As those indexes don't contain references to the row, what is it locking? -- Thom -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
