expression/expressions: add column count check.
expression/expressions: add column count check.

kyle-wang/tidb,CodeRushing/tidb,anywhy/tidb,anywhy/tidb,XuHuaiyu/tidb,zs634134578/tidb,coocood/tidb,qiuyesuifeng/tidb,wusphinx/tidb,silenceper/tidb,tiancaiamao/tidb,ngaut/tidb,silentred/tidb,ngaut/tidb,c4pt0r/tidb,coocood/tidb,wusphinx/tidb,qhsong/tidb,ueizhou/tidb,EvilMcJerkface/tidb,8cbx/tidb,zimulala/tidb,pingcap/tidb,c4pt0r/tidb,kyle-wang/tidb,ueizhou/tidb,yangwenmai/tidb,simon-xia/tidb,mccxj/tidb,gaocegege/tidb,louishust/tidb,c4pt0r/tidb,silentred/tidb,myrice/tidb,pingcap/tidb,netroby/tidb,ngaut/tidb,mccxj/tidb,JinheLin/tidb,spongedu/tidb,cosmtrek/tidb,kyle-wang/tidb,silenceper/tidb,tiancaiamao/tidb,andelf/tidb,kyle-wang/tidb,Nify/tidb,cosmtrek/tidb,pingcap/tidb,gaocegege/tidb,JinheLin/tidb,c4pt0r/tidb,netroby/tidb,ngaut/tidb,Cofyc/tidb,yangwenmai/tidb,liyu4/tidb,spongedu/tidb,myrice/tidb,yuanwhy/tidb,EvilMcJerkface/tidb,astaxie/tidb,yuanwhy/tidb,louishust/tidb,ngaut/tidb,CodeRushing/tidb,simon-xia/tidb,pingcap/tidb,c4pt0r/tidb,ming-relax/tidb,pingcap/tidb,8cbx/tidb,astaxie/tidb,XuHuaiyu/tidb,kyle-wang/tidb,qiuyesuifeng/tidb,c4pt0r/tidb,kyle-wang/tidb,pingcap/tidb,ming-relax/tidb,zimulala/tidb,Nify/tidb,andelf/tidb,zs634134578/tidb,ngaut/tidb,liyu4/tidb,qhsong/tidb,Cofyc/tidb