Fatal error while installing - Mailing list pgsql-general

I seem to get this error "user postgres could not be created, user
account already exists" when trying to install postgres. Anyone knows
how to fix this?

Erik Jones wrote:
> Erik Jones wrote:
>> Ok, consider the following table definition:
>>
>> CREATE TABLE stats (
>> id SERIAL PRIMARY KEY,
>> hits bigint default 0,
>> clickthrus bigint default 0,
>> referrals bigint default 0);
>>
>>
>> Now, this table has a lot of rows that are constantly being updated
>> by queries of the following form:
>>
>> UPDATE stats
>> SET clickthrus = clickthrus + #
>> WHERE id = blah;  -- sub various values for # and blah
>>
>> There can be, and often are,  multiple updates for the same row
>> coming in at the same time,  but never for the same field.  My
>> understanding of the locking involved is that updates take out
>> row-exclusive locks to prevent other transactions from modifying the
>> data and to serialize with other updates.  So, multiple update
>> statements to the same row come in, the first to arrive is granted a
>> row-exclusive lock and the other wait.  When the first is finished
>> and commits, the second to have arrived get the lock, and so forth.
>> Here is what I am seeing all through my logs:
>>
>> 2006-08-29 03:17:25 CDT 16074 192.168.1.173(35190):STATEMENT: ABORT
>> 2006-08-29 03:17:25 CDT 8553 192.168.1.168(42707):ERROR: deadlock
>> detected
>> 2006-08-29 03:17:25 CDT 8553 192.168.1.168(42707):DETAIL: Process
>> 8553 waits for ShareLock on transaction 1548224183; blocked by
>> process 5499.
>> Process 5499 waits for ShareLock on transaction 1548224182; blocked
>> by process 8553.
>> 2006-08-29 03:17:25 CDT 8553 192.168.1.168(42707):STATEMENT: UPDATE
>> stats
>> SET hits = hits + 3
>> WHERE id = 271524;
>>
>> or,
>>
>> 2006-08-29 08:47:31 CDT 12479 192.168.1.168(46125):ERROR: deadlock
>> detected
>> 2006-08-29 08:47:31 CDT 12479 192.168.1.168(46125):DETAIL: Process
>> 12479 waits for ExclusiveLock on tuple (3024,45) of relation 33942 of
>> database 33325; blocked by process 12513
>> .
>> Process 12513 waits for ShareLock on transaction 1550567046; blocked
>> by process 12495.
>> Process 12495 waits for ShareLock on transaction 1550569729; blocked
>> by process 12479.
>> 2006-08-29 08:47:31 CDT 12479 192.168.1.168(46125):STATEMENT: UPDATE
>> stats
>> SET click_thrus = clickthrus + 1
>> WHERE id = 275359;
>>
>> What's with ShareLock s on transactions?  Where do those come from?
>>
>
> I should also note that each of those updates occurs in it's own
> transactions, but that they do not attempt to modify any other rows in
> that table before commiting.  They do,  however, delete rows in
> another common table (where they pulled the stat counts from), but the
> rows they delete are disjunct.
>
> The whole process/algorithm is such:
>
> 1.  Get rows matching X from temp table.
> 2.  Accumulate values from X and update row and field corresponding to
> X in stats table.
> 3.  Delete rows collected in step one.
> 4.  Commit.
> 5.  Repeat from step 1.
>
> With multiple processes using the same algo and tables but for
> different values of X.
>
>