Neto pr wrote: > When creating index on table of approximately 10GB of data, the DBMS hangs (I think), > because even after waiting 10 hours there was no return of the command. > It happened by creating Hash indexes and B + tree indexes. > However, for some columns, it was successfully (L_RETURNFLAG, L_PARTKEY).
> If someone has a hint how to speed up index creation so that it completes successfully.
Look if CREATE INDEX is running or waiting for a lock (check the "pg_locks" table, see if the backend consumes CPU time).
In this moment now, there is an index being created in the Lineitem table (+ - 10 Gb), and apparently it is locked, since it started 7 hours ago. I've looked at the pg_locks table and look at the result, it's with "ShareLock" lock mode. Is this blocking correct? or should it be another type?
Before creating the index, should I set the type of transaction lock? What? -------------------------------------------------------------------------------------------
SELECT L.mode, c.relname, locktype, l.GRANTED, l.transactionid, virtualtransaction FROM pg_locks l, pg_class c where c.oid = l.relation
-------------- RESULT --------------------------------------------------------------
AccessShareLock
pg_class_tblspc_relfilenode_index
relation
TRUE
(null)
3/71
AccessShareLock
pg_class_relname_nsp_index
relation
TRUE
(null)
3/71
AccessShareLock
pg_class_oid_index
relation
TRUE
(null)
3/71
AccessShareLock
pg_class
relation
TRUE
(null)
3/71
AccessShareLock
pg_locks
relation
TRUE
(null)
3/71
ShareLock
lineitem
relation
TRUE
(null)
21/3769
Maybe there is a long-running transaction that blocks the ACCESS EXCLUSIVE lock required. It could also be a prepared transaction.