"MYSQL" Select from Group by

• GROUP BY

Mysql> SELECT * from t_user GROUP by LVL; +-----+-------+----------+------+--------+| UID | uname | Tel      | lvl  | salart |+-----+-------+----------+------+--------+|   1 | Alex  | 23131231 | A    |   1100 | |   3 | Kit   | 87416574 | B    |   | |   4 | Poker | 41874521 | C    |   1560 |+-----+-------+----------+------+--------+mysql> select lvl from T_user group by LVL; +------+| LVL  |+------+| A    | | B    | | C    |+------+

• Group by + Group_concat ()

Mysql>Select Lvl,group_concat (salart) from T_user Group by LVL;+------+----------------------+| Lvl | Group_concat (Salart) |+------+----------------------+| A | 1100,4300 | | B | 1200 | | C | 1560 |+------+----------------------+3 rowsinchSet (0.00sec) MySQL>Select Lvl,group_concat (UID) as salary from T_user Group by LVL;+------+--------+| Lvl | Salary |+------+--------+| A | | | B | 3 | | C | 4 |+------+--------+3 rowsinchSet (0.00sec) MySQL>Select Lvl,group_concat (salart) from T_user Group by LVL;+------+----------------------+| Lvl | Group_concat (Salart) |+------+----------------------+| A | 1100,4300 | | B | 1200 | | C | 1560 |+------+----------------------+3 rowsinchSet (0.00sec) MySQL>Select Lvl,group_concat (Salart) as salary from T_user Group by LVL;+------+-----------+| Lvl | Salary |+------+-----------+| A | 1100,4300 | | B | 1200 | | C | 1560 |+------+-----------+3 rowsinchSet (0.00 sec)

• #group by + aggregate function

mysql> Select Lvl,group_concat (UID) as salary from T_user Group by LVL; +------+--------+| Lvl  | Salary |+------+--------+| A    | |    B    | 3      | | C    | 4 in       Set (0.00 sec) MySQL> select Lvl,count (UID) as salary from T_user Group by lvl;< /c10>+------+--------+| Lvl  | Salary |+------+--------+| A    |      2 | | B    |      1 | | C    |       in Set (0.00 sec)

• #group by + have

Mysql> Select Lvl,group_concat (salart) from T_user GROUP by LVL have Group_concat (salart) =1200;+------+----------------------+| Lvl | Group_concat (Salart) |+------+----------------------+| B | |+------+----------------------+1 rowinchSet (0.00sec) MySQL> select Lvl,group_concat (salart) from T_user GROUP by LVL have Group_concat (salart) =1100;+------+----------------------+| Lvl | Group_concat (Salart) |+------+----------------------+| A | 1100,4300 |+------+----------------------+1 rowinchSet (0.00sec) MySQL>MySQL>Select Lvl,count (UID) as salary from T_user Group by LVL;+------+--------+| Lvl | Salary |+------+--------+|      A | 2 | |      B | 1 | |      C | 1 |+------+--------+3 rowsinchSet (0.00sec) MySQL> select Lvl,count (UID) as salary from T_user Group by LVL have count (UID) >1;+------+--------+| Lvl | Salary |+------+--------+|      A | 2 |+------+--------+1 rowinchSet (0.00 sec)

"MYSQL" Select from Group by