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mysql> insert into voteItem values (null,'bbbbb',0);
Query OK, 1 row affected (0.06 sec)
mysql> select v.id,v.title,count(t.id)
-> from voteItem v left join ticket t on v.id=t.voteItemID
-> group by v.id,v.title;
+----+-------+-------------+
| id | title | count(t.id) |
+----+-------+-------------+
| 1 | aaaaa | 1 |
| 2 | bbbbb | 0 |
+----+-------+-------------+
2 rows in set (0.00 sec)
mysql> create table voteItem
-> (
-> id INT NOT NULL AUTO_INCREMENT PRIMARY KEY,
-> title varchar(30),
-> ticketNumber int
-> );
Query OK, 0 rows affected (0.09 sec)
mysql>
mysql> create table ticket(
-> id INT NOT NULL AUTO_INCREMENT PRIMARY KEY,
-> voteItemID INT references voteItem(id) ,
-> ip varchar(30)
-> );
Query OK, 0 rows affected (0.09 sec)
mysql>
mysql> insert into voteItem values (null,'aaaaa',0);
Query OK, 1 row affected (0.03 sec)
mysql>
mysql> select * from voteItem;
+----+-------+--------------+
| id | title | ticketNumber |
+----+-------+--------------+
| 1 | aaaaa | 0 |
+----+-------+--------------+
1 row in set (0.00 sec)
mysql>
mysql> DELIMITER |
mysql>
mysql> CREATE TRIGGER testref AFTER INSERT ON ticket
-> FOR EACH ROW BEGIN
-> update voteItem set ticketNumber=ticketNumber+1 where id = new.v
oteItemID;
-> END;
-> |
Query OK, 0 rows affected (0.09 sec)
mysql>
mysql> DELIMITER ;
mysql>
mysql> insert into ticket values (null,1,'127.0.0.1');
Query OK, 1 row affected (0.08 sec)
mysql> select * from ticket;
+----+------------+-----------+
| id | voteItemID | ip |
+----+------------+-----------+
| 1 | 1 | 127.0.0.1 |
+----+------------+-----------+
1 row in set (0.00 sec)
mysql> select * from voteItem;
+----+-------+--------------+
| id | title | ticketNumber |
+----+-------+--------------+
| 1 | aaaaa | 1 |
+----+-------+--------------+
1 row in set (0.00 sec)
DELIMITER |
CREATE TRIGGER testref AFTER INSERT ON ticket
FOR EACH ROW BEGIN
update voteItem set ticketNumber=ticketNumber+1 where id = new.voteItemID;
END;
|
DELIMITER ;