Re: [HACKERS] "union all" query consumes all memory

2013-11-14 Thread Tom Lane
Pavel Stehule writes: > one my customer reported a "out of memory" issue. After investigation he > found a main problem in large query that uses a lot of union all queries. > He wrote a self test: > do $$ > declare i integer; str text=''; > begin > for i in 1..1000 loop > str := str || 'unio

[HACKERS] "union all" query consumes all memory

2013-11-14 Thread Pavel Stehule
Hello, one my customer reported a "out of memory" issue. After investigation he found a main problem in large query that uses a lot of union all queries. He wrote a self test: do $$ declare i integer; str text=''; begin for i in 1..1000 loop str := str || 'union all select i,i,i from generat