Csaba Nagy wrote: > session_1=> create table test (col smallint primary key); > NOTICE: CREATE TABLE / PRIMARY KEY will create implicit index > "test_pkey" for table "test" > CREATE TABLE > session_1=> begin; > BEGIN > cnagy=> insert into test values (1); > INSERT 165068987 1 > > session_2=> begin; > BEGIN > session_2=> insert into test values (1); > > [session_2 is now waiting]
This only happens because of the unique index. There's no predicate locking involved. The btree code goes some lengths to make this work; it would be probably simple to modify this to support MERGE or REPLACE on the limited cases where there's a UNIQUE index. Tom has already said this twice (on this thread only; he has already said it before IIRC.) -- Alvaro Herrera http://www.CommandPrompt.com/ PostgreSQL Replication, Consulting, Custom Development, 24x7 support ---------------------------(end of broadcast)--------------------------- TIP 5: don't forget to increase your free space map settings
