utils: document return values
utils: document return values

jockchou/mysql,tmulchay/mysql,cxflag203/mysql,helight/helight_code,henrylee2cn/mysql,segmentio/mysql,sunjian1/mysql,helight/helight_code,aperera/mysql,helight/helight_code,methane/mysql,chinanjjohn2012/mysql,methane/mysql,go-sql-driver/mysql,yyljlyy/mysql,helight/helight_code,VividCortex/mysql,cw2018/mysql,roth1002/mysql,wfxiang08/mysql,VividCortex/mysql,netroby/mysql,eXcomm/gomysql,yonglehou/mysql,eklitzke/mysql,LightKool/mysql-go,bookerzzz/mysql,helight/helight_code,Vorstack/mysql,bookerzzz/mysql,helight/helight_code,springning/mysql,rafaeljusto/mysql,rlowe/mysql,beego/mysql,zhgo/mysql,Frca/mysql,hebihui/mysql,nanata1115/mysql,siriele/mysql,hyperworks/mysql,helight/helight_code,segmentio/mysql,helight/helight_code,joshuaprunier/mysql,dalinaum/go-mysql-driver,muthusubbu459/mysql,LightKool/mysql-go,Freeaqingme/golang-sql-driver-mysql,helight/helight_code,Go-SQL-Driver/MySQL