MySQL 显示行号,以及分组排序
Contents
“MySQL 显示行号,以及分组排序”
CREATE TABLE my_tb (
id int(11) NOT NULL AUTO_INCREMENT,
parent_code varchar(255) DEFAULT NULL,
code varchar(255) DEFAULT NULL,
PRIMARY KEY (id)
) ENGINE=InnoDB AUTO_INCREMENT=8 DEFAULT CHARSET=utf8;
INSERT INTO `my_tb` ( `parent_code`, `code`) VALUES ('01', '001');
INSERT INTO `my_tb` ( `parent_code`, `code`) VALUES ('01', '002');
INSERT INTO `my_tb` ( `parent_code`, `code`) VALUES ('02', '001');
INSERT INTO `my_tb` ( `parent_code`, `code`) VALUES ('01', '003');
INSERT INTO `my_tb` ( `parent_code`, `code`) VALUES ('02', '002');
INSERT INTO `my_tb` ( `parent_code`, `code`) VALUES ('03', '001');
INSERT INTO `my_tb` ( `parent_code`, `code`) VALUES ('04', '001');
-- 生成 行号
select @r:=@r+1 as row_num , a.* from my_tb a ,(select @r:=0) b
-- 生成 分组排序号
select
@group_row:=CASE when @parent_code=a.parent_code then @group_row+1 else 1 end as groupRow,
@parent_code:=a.parent_code as parent_code,
a.code
from my_tb a ,( select @group_row:=1, @parent_code:='') as b
ORDER BY a.parent_code , a.code
查询结果
"groupRow" "parent_code" "code"
"1" "01" "001"
"2" "01" "002"
"3" "01" "003"
"1" "02" "001"
"2" "02" "002"
"1" "03" "001"
"1" "04" "001"
Author -
LastMod 0001-01-01