planner: do not eliminate group_concat in aggregate elimination (#9967)#9969

Merged

zz-jason merged 3 commits intopingcap:release-2.1from XuHuaiyu:release-2.1

Apr 1, 2019

+36

Commits on Apr 1, 2019

planner: do not eliminate group_concat in aggregate elimination (pingcap#9967 )
XuHuaiyu
committed
Merge branch 'release-2.1' of https://github.com/pingcap/tidb into release-2.1
XuHuaiyu
committed
remove useless line
XuHuaiyu
committed