rewrite db base
rewrite db base

maxzhang/thinkjs,thinkjs/thinkjs,akira-cn/thinkjs,75team/thinkjs,75team/thinkjs,Qihoo360/thinkjs,snadn/thinkjs,akira-cn/thinkjs,akira-cn/thinkjs,75team/thinkjs,maxzhang/thinkjs,maxzhang/thinkjs