Hi, A problem related with view was reported from a user. I narrowed down the problem and found it was related to some usage of views: (note that with/without limit is not relevant)
test=# select count(a.*) from pg_indexes a limit 10; server closed the connection unexpectedly This probably means the server terminated abnormally before or while processing the request. The connection to the server was lost. Attempting reset: Failed. !> Here is a backtrace on 7.4-stable and Linux: Program received signal SIGSEGV, Segmentation fault. bms_is_empty (a=0x10) at bitmapset.c:519 519 nwords = a->nwords; (gdb) where #0 bms_is_empty (a=0x10) at bitmapset.c:519 #1 0x08124fc1 in add_vars_to_targetlist (root=0x82cffc0, vars=0x82ebf20, where_needed=0x82ebf38) at initsplan.c:149 #2 0x08124f70 in build_base_rel_tlists (root=0x82cffc0, final_tlist=0x82ebec0) at initsplan.c:122 #3 0x08125cc5 in query_planner (root=0x82cffc0, tlist=0x82ebec0, tuple_fraction=0, cheapest_path=0xbfffe428, sorted_path=0xbfffe42c) at planmain.c:134 #4 0x081268cf in grouping_planner (parse=0x82cffc0, tuple_fraction=10) at planner.c:895 #5 0x081260f9 in subquery_planner (parse=0x82cffc0, tuple_fraction=0) at planner.c:315 #6 0x08125e70 in planner (parse=0x82cffc0, isCursor=0, cursorOptions=0) at planner.c:119 #7 0x081525df in pg_plan_query (querytree=0x82cffc0) at postgres.c:589 #8 0x08152668 in pg_plan_queries (querytrees=0x82ebd68, needSnapshot=0 '\000') at postgres.c:656 #9 0x08152868 in exec_simple_query ( query_string=0x82cfa38 "select count(a.*) from pg_indexes a limit 10;") at postgres.c:814 #10 0x08154ba9 in PostgresMain (argc=4, argv=0x8285ca8, username=0x8285c78 "t-ishii") at postgres.c:2868 #11 0x0813463d in BackendFork (port=0x8292ee0) at postmaster.c:2558 ---Type <return> to continue, or q <return> to quit--- #12 0x08133ed5 in BackendStartup (port=0x8292ee0) at postmaster.c:2201 #13 0x08132838 in ServerLoop () at postmaster.c:1113 #14 0x081323a0 in PostmasterMain (argc=3, argv=0x8283ef0) at postmaster.c:891 #15 0x08108d3f in main (argc=3, argv=0xbffff5c4) at main.c:214 #16 0x400f113f in __libc_start_main (main=0x8108b70 <main>, argc=3, ubp_av=0xbffff5c4, init=0x806e458 <_init>, fini=0x81c1760 <_fini>, rtld_fini=0x4000c770 <_dl_fini>, stack_end=0xbffff5bc) at ../sysdeps/generic/libc-start.c:129 ---------------------------(end of broadcast)--------------------------- TIP 4: Don't 'kill -9' the postmaster