Why this lock? - Mailing list pgsql-general

I then did a "vacuum analyze" on that table and rerun the query (process 9732) to create the index.  It soon stalled again and the following result shows that proces 17434 is blocking it:

locktype  | database | relation | page | tuple | virtualxid | transactionid | classid | objid | objsubid | virtualtransaction | pid  |   mode    | granted | fastpath | virtualtransaction |  pid  |     mode      | granted
------------+----------+----------+------+-------+------------+---------------+---------+-------+----------+--------------------+------+-----------+---------+----------+--------------------+-------+---------------+---------
 virtualxid |          |          |      |       | 6/24891    |               |         |       |          | 7/27906            | 9732 | ShareLock | f       | f        | 6/24891            | 17434 | ExclusiveLock | t

Now my questions:

What would cause such a lock?

What can I do to remove the lock without stopping the long-running process which started before the query to create the index?  I suppose I just have to wait for the first process to finish...

Regards

Johann

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