@i：類型java定義的變量
@i:=0：這里類似給i初始化值為0
@i:=@i+1 ：每次從0開始遞增+1

SELECT (@i:=@i+1) as id,TDLINE FROM YXGL_QX_LINES_BEIZHU,(select   @i:=0)as it where ZDBID ='1248287578994640896';