mongos> db.hourly_stats.findOne({log_file_name:/^2012-02-02/, $and: [{sub_key:null}, {sub_key:{$exists:true}}], publish:{$gt:0}})
^CFri Feb 10 03:08:13 Error: error doing query: unknown shell/collection.js:151
^CFri Feb 10 03:10:06 ERROR: MessagingPort::call() wrong id got:1b4 expect:1b6
  toSend op: 2004
  response msgid:269662
  response len:  203
  response op:  1
  remote: 127.0.0.1:27017
Fri Feb 10 03:10:06   Assertion failure false util/net/message_port.cpp 245
0x4a2196 0x4a4bfb 0x5ec8b2 0x5ecae4 0x4c15f4 0x4e515d 0x4b960c 0x4cffa1 0x4c1883 0x4c2392 0x4d144a 0x471dd9 0x475232 0x4764c6 0x7f93b9b8f30d 0x46efc9
 bin/mongo(_ZN5mongo12sayDbContextEPKc+0x96) [0x4a2196]
 bin/mongo(_ZN5mongo8assertedEPKcS1_j+0xfb) [0x4a4bfb]
 bin/mongo(_ZN5mongo13MessagingPort4recvERKNS_7MessageERS1_+0x272) [0x5ec8b2]
 bin/mongo(_ZN5mongo13MessagingPort4callERNS_7MessageES2_+0x34) [0x5ecae4]
 bin/mongo(_ZN5mongo18DBClientConnection4callERNS_7MessageES2_bPSs+0x34) [0x4c15f4]
 bin/mongo(_ZN5mongo14DBClientCursor4initEv+0xad) [0x4e515d]
 bin/mongo(_ZN5mongo12DBClientBase5queryERKSsNS_5QueryEiiPKNS_7BSONObjEii+0x3ac) [0x4b960c]
 bin/mongo(_ZN5mongo18DBClientConnection5queryERKSsNS_5QueryEiiPKNS_7BSONObjEii+0xa1) [0x4cffa1]
 bin/mongo(_ZN5mongo17DBClientInterface5findNERSt6vectorINS_7BSONObjESaIS2_EERKSsNS_5QueryEiiPKS2_i+0xa3) [0x4c1883]
 bin/mongo(_ZN5mongo17DBClientInterface7findOneERKSsRKNS_5QueryEPKNS_7BSONObjEi+0x72) [0x4c2392]
 bin/mongo(_ZN5mongo18DBClientConnection10runCommandERKSsRKNS_7BSONObjERS3_i+0x7a) [0x4d144a]
 bin/mongo(_Z21sayReplSetMemberStatev+0x399) [0x471dd9]
 bin/mongo(_Z5_mainiPPc+0x26c2) [0x475232]
 bin/mongo(main+0x26) [0x4764c6]
 /lib/x86_64-linux-gnu/libc.so.6(__libc_start_main+0xed) [0x7f93b9b8f30d]
 bin/mongo(_ZNSt15basic_streambufIcSt11char_traitsIcEE6xsputnEPKcl+0x59) [0x46efc9]
> exit
bye