expression: fix date_add interval month,year diffs from mysql (#8988)#9284

Merged

zimulala merged 1 commit intopingcap:release-2.1from haplone:release-2.1_date_add

Feb 13, 2019

+120-12

Commits on Feb 12, 2019

expression: fix date_add interval month,year diffs from mysql (pingcap#8988 )
haplone
committed