from my log:
20946:20091005:160035 [Z3005] Query failed: [0] PGRES_FATAL_ERROR:ERROR: duplicate key value violates unique constraint "trends_pkey"
[insert into trends (clock,itemid,num,value_min,value_avg,value_max) values (1254751200,22170,1,965.478261,965.478261,965.478261)]
20946:20091005:160035 [Z3005] Query failed: [0] PGRES_FATAL_ERROR:ERROR: current transaction is aborted, commands ignored until end of transaction block
[update items set nextcheck=1254751227,prevvalue=lastvalue,prevorgvalue='4569905065.000000',lastvalue='965.478261',lastclock=1254751222 where itemid=22170]
20946:20091005:160035 [Z3005] Query failed: [0] PGRES_FATAL_ERROR:ERROR: current transaction is aborted, commands ignored until end of transaction block
[select distinct function,parameter,itemid,lastvalue from functions where itemid=22170]
20347:20091005:160036 One child process died. Exiting ...