Fatal error while installing
2006-09-01 05:21:51 GMT
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.(Continue reading)
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