mysql> #子查询
mysql> #子查询是嵌套在查询内部的查询;
mysql>
mysql> #使用比较运算符的子查询;
mysql> #求价格平均值;
mysql> SELECT AVG(goods_price) FROM tdb_goods;
mysql> SELECT AVG(goods_price) FROM tdb_goods;
+------------------+
| AVG(goods_price) |
+------------------+
| 5636.3636364 |
+------------------+
1 row in set (0.03 sec)
mysql> #四舍五入
mysql> #保留到小数点后两位; mysql> SELECT
ROUND
(AVG(goods_price),2) FROM tdb_goods;
+---------------------------+
|
ROUND
(AVG(goods_price),2) |
+---------------------------+
| 5636.36 |
+---------------------------+
1 row in set (0.02 sec)
mysql> SELECT goods_id,goods_price FROM tdb_goods WHERE goods_price>=5636.36;
+----------+-------------+
| goods_id | goods_price |
+----------+-------------+
| 3 | 8499.000 |
| 7 | 7999.000 |
| 13 | 9188.000 |
| 17 | 28888.000 |
| 18 | 6999.000 |
| 20 | 6888.000 |
| 21 | 6999.000 |
+----------+-------------+
7 rows in set (0.00 sec)
mysql> #通过子查询实现上式;
mysql> SELECT goods_id,goods_price FROM tdb_goods WHERE goods_price>=(SELECT
ROUND
(AVG(goods_price),2)
FROM tdb_goods);
+----------+-------------+
| goods_id | goods_price |
+----------+-------------+
| 3 | 8499.000 |
| 7 | 7999.000 |
| 13 | 9188.000 |
| 17 | 28888.000 |
| 18 | 6999.000 |
| 20 | 6888.000 |
| 21 | 6999.000 |
+----------+-------------+
7 rows in set (0.03 sec)
mysql> SELECT goods_price FROM tdb_goods WHERE goods_cate='超级本';
+-------------+
| goods_price |
+-------------+
| 4999.000 |
| 4299.000 |
| 7999.000 |
+-------------+
3 rows in set (0.00 sec)
mysql> SELECT * FROM tdb_goods WHERE goods_cate='超级本'\G;
*************************** 1. row ***************************
goods_id: 5
goods_name: X240(20ALA0EYCD) 12.5英寸超极本
goods_cate: 超级本
brand_name: 联想
goods_price: 4999.000
is_show: 1
is_saleoff: 0
*************************** 2. row ***************************
goods_id: 6
goods_name: U330P 13.3英寸超极本
goods_cate: 超级本
brand_name: 联想
goods_price: 4299.000
is_show: 1
is_saleoff: 0
*************************** 3. row ***************************
goods_id: 7
goods_name: SVP13226SCB 13.3英寸触控超极本
goods_cate: 超级本
brand_name: 索尼
goods_price: 7999.000
is_show: 1
is_saleoff: 0
3 rows in set (0.00 sec)
ERROR:
No query specified
mysql> SELECT goods_id,goods_name,goods_price FROM tdb_goods WHERE goods_price>
(SELECT goods_price FROM tdb_goods WHERE goods_cate='超级本');
ERROR 1242 (21000): Subquery returns more than 1 row
mysql> #鉴于上述错误,子查询用三个关键字修饰
mysql> SELECT goods_id,goods_name,goods_price FROM tdb_goods WHERE goods_price>ANY
(SELECT goods_price FROM tdb_goods WHERE goods_cate='超级本');
+----------+----------------------------------+-------------+
| goods_id | goods_name | goods_price |
+----------+----------------------------------+-------------+
| 2 | Y400N 14.0英寸笔记本电脑 | 4899.000 |
| 3 | G150TH 15.6英寸游戏本 | 8499.000 |
| 5 | X240(20ALA0EYCD) 12.5英寸超极本 | 4999.000 |
| 7 | SVP13226SCB 13.3英寸触控超极本 | 7999.000 |
| 13 | iMac ME086CH/A 21.5英寸一体电脑 | 9188.000 |
| 16 | PowerEdge T110 II服务器 | 5388.000 |
| 17 | Mac Pro MD878CH/A 专业级台式电脑 | 28888.000 |
| 18 | HMZ-T3W 头戴显示设备 | 6999.000 |
| 20 | X3250 M4机架式服务器 2583i14 | 6888.000 |
| 21 | HMZ-T3W 头戴显示设备 | 6999.000 |
+----------+----------------------------------+-------------+
10 rows in set (0.00 sec)
mysql> SELECT goods_id,goods_name,goods_price FROM tdb_goods WHERE goods_price>ALL
(SELECT goods_price FROM tdb_goods WHERE goodscate='超级本');
+----------+----------------------------------+-------------+
| goods_id | goods_name | goods_price |
+----------+----------------------------------+-------------+
| 3 | G150TH 15.6英寸游戏本 | 8499.000 |
| 13 | iMac ME086CH/A 21.5英寸一体电脑 | 9188.000 |
| 17 | Mac Pro MD878CH/A 专业级台式 脑 | 28888.000 |
+----------+----------------------------------+-------------+
3 rows in set (0.01 sec)
mysql> #使用 in 和not in 引发的子查询;
mysql> #EXIST 和not EXIST 引发的子查询
mysql> #创建商品标签数据表:
mysql> CREATE TABLE IF NOT EXISTS tdb_goods_cate(
-> cate_id SMALLINT UNSIGNED PRIMARY KEY AUTO_INCREMENT,
-> cate_name VARCHAR(40) NOT NULL
-> );
Query OK, 0 rows affected (0.18 sec)
mysql> #得到商品分类;
mysql> SELECT goods_cate FROM tdb_goods GROUP BY goods_cate;
+---------------+
| goods_cate |
+---------------+
| 台式机 |
| 平板电脑 |
| 服务器/工作站 |
| 游戏本 |
| 笔记本 |
| 笔记本配件 |
| 超级本 |
+---------------+
7 rows in set (0.00 sec)
mysql> #将查询的结果写入的数据表中、
mysql> SELECT * FROM tdb_goods_cate;
Empty
set (0.00 sec)
mysql> DESC tdb_goods_cate;
+-----------+----------------------+------+-----+---------+----------------+
| Field | Type | Null | Key | Default | Extra |
+-----------+----------------------+------+-----+---------+----------------+
| cate_id | smallint(5) unsigned | NO | PRI | NULL | auto_increment |
| cate_name | varchar(40) | NO | | NULL | |
+-----------+----------------------+------+-----+---------+----------------+
2 rows in set (0.01 sec)
mysql> INSERT tdb_goods_cate(cate_name) SELECT goods_cate FROM tdb_goods GROUP BY goods_cate;
Query OK, 7 rows affected (0.04 sec)
Records: 7 Duplicates: 0 Warnings: 0
mysql> SELECT * FROM tdb_goods_cate;
+---------+---------------+
| cate_id | cate_name |
+---------+---------------+
| 1 | 台式机 |
| 2 | 平板电脑 |
| 3 | 服务器/工作站 |
| 4 | 游戏本 |
| 5 | 笔记本 |
| 6 | 笔记本配件 |
| 7 | 超级本 |
+---------+---------------+
7 rows in set (0.00 sec)
mysql> #参照分类表更新商品表、
mysql> UPDATE tdb_goods INNER JOIN tdb_goods_cate ON goods_cate=cate_name SET goods_cate=cate_id;
Query OK, 22 rows affected (0.21 sec)
Rows matched: 22 Changed: 22 Warnings: 0
mysql> SELECT * FROM tdb_goods\G;
*************************** 1. row ***************************
goods_id: 1
goods_name: R510VC 15.6英寸笔记本
goods_cate: 5
brand_name: 华硕
goods_price: 3399.000
is_show: 1
is_saleoff: 0
*************************** 2. row ***************************
goods_id: 2
goods_name: Y400N 14.0英寸笔记本电脑
goods_cate: 5
brand_name: 联想
goods_price: 4899.000
is_show: 1
is_saleoff: 0
*************************** 3. row ***************************
goods_id: 3
goods_name: G150TH 15.6英寸游戏本
goods_cate: 4
brand_name: 雷神
goods_price: 8499.000
is_show: 1
is_saleoff: 0
*************************** 4. row ***************************
goods_id: 4
goods_name: X550CC 15.6英寸笔记本
goods_cate: 5
brand_name: 华硕
goods_price: 2799.000
is_show: 1
is_saleoff: 0
*************************** 5. row ***************************
goods_id: 5
goods_name: X240(20ALA0EYCD) 12.5英寸超极本
goods_cate: 7
brand_name: 联想
goods_price: 4999.000
is_show: 1
is_saleoff: 0
*************************** 6. row ***************************
goods_id: 6
goods_name: U330P 13.3英寸超极本
goods_cate: 7
brand_name: 联想
goods_price: 4299.000
is_show: 1
is_saleoff: 0
*************************** 7. row ***************************
goods_id: 7
goods_name: SVP13226SCB 13.3英寸触控超极本
goods_cate: 7
brand_name: 索尼
goods_price: 7999.000
is_show: 1
is_saleoff: 0
*************************** 8. row ***************************
goods_id: 8
goods_name: iPad mini MD531CH/A 7.9英寸平板电脑
goods_cate: 2
brand_name: 苹果
goods_price: 1998.000
is_show: 1
is_saleoff: 0
*************************** 9. row ***************************
goods_id: 9
goods_name: iPad Air MD788CH/A 9.7英寸平板电脑 (16G WiFi版)
goods_cate: 2
brand_name: 苹果
goods_price: 3388.000
is_show: 1
is_saleoff: 0
*************************** 10. row ***************************
goods_id: 10
goods_name: iPad mini ME279CH/A 配备 Retina 显示屏 7.9英寸平板电脑 (16G WiFi版)
goods_cate: 2
brand_name: 苹果
goods_price: 2788.000
is_show: 1
is_saleoff: 0
*************************** 11. row ***************************
goods_id: 11
goods_name: IdeaCentre C340 20英寸一体电脑
goods_cate: 1
brand_name: 联想
goods_price: 3499.000
is_show: 1
is_saleoff: 0
*************************** 12. row ***************************
goods_id: 12
goods_name: Vostro 3800-R1206 台式电脑
goods_cate: 1
brand_name: 戴尔
goods_price: 2899.000
is_show: 1
is_saleoff: 0
*************************** 13. row ***************************
goods_id: 13
goods_name: iMac ME086CH/A 21.5英寸一体电脑
goods_cate: 1
brand_name: 苹果
goods_price: 9188.000
is_show: 1
is_saleoff: 0
*************************** 14. row ***************************
goods_id: 14
goods_name: AT7-7414LP 台式电脑 (i5-3450四核 4G 500G 2G独显 DVD 键鼠 Linux )
goods_cate: 1
brand_name: 宏碁
goods_price: 3699.000
is_show: 1
is_saleoff: 0
*************************** 15. row ***************************
goods_id: 15
goods_name: Z220SFF F4F06PA工作站
goods_cate: 3
brand_name: 惠普
goods_price: 4288.000
is_show: 1
is_saleoff: 0
*************************** 16. row ***************************
goods_id: 16
goods_name: PowerEdge T110 II服务器
goods_cate: 3
brand_name: 戴尔
goods_price: 5388.000
is_show: 1
is_saleoff: 0
*************************** 17. row ***************************
goods_id: 17
goods_name: Mac Pro MD878CH/A 专业级台式电脑
goods_cate: 3
brand_name: 苹果
goods_price: 28888.000
is_show: 1
is_saleoff: 0
*************************** 18. row ***************************
goods_id: 18
goods_name: HMZ-T3W 头戴显示设备
goods_cate: 6
brand_name: 索尼
goods_price: 6999.000
is_show: 1
is_saleoff: 0
*************************** 19. row ***************************
goods_id: 19
goods_name: 商务双肩背包
goods_cate: 6
brand_name: 索尼
goods_price: 99.000
is_show: 1
is_saleoff: 0
*************************** 20. row ***************************
goods_id: 20
goods_name: X3250 M4机架式服务器 2583i14
goods_cate: 3
brand_name: IBM
goods_price: 6888.000
is_show: 1
is_saleoff: 0
*************************** 21. row ***************************
goods_id: 21
goods_name: HMZ-T3W 头戴显示设备
goods_cate: 6
brand_name: 索尼
goods_price: 6999.000
is_show: 1
is_saleoff: 0
*************************** 22. row ***************************
goods_id: 22
goods_name: 商务双肩背包
goods_cate: 6
brand_name: 索尼
goods_price: 99.000
is_show: 1
is_saleoff: 0
22 rows in set (0.00 sec)
ERROR:
No query specified
mysql> SELECT * FROM tdb_goods_brands;
+----------+------------+
| brand_id | brand_name |
+----------+------------+
| 1 | IBM |
| 2 | 华硕 |
| 3 | 宏碁 |
| 4 | 惠普 |
| 5 | 戴尔 |
| 6 | 索尼 |
| 7 | 联想 |
| 8 | 苹果 |
| 9 | 雷神 |
+----------+------------+
9 rows in set (0.00 sec)
mysql> SHOW COLUMNS FROM tdb_goods;
+-------------+------------------------+------+-----+---------+----------------+
| Field | Type | Null | Key | Default | Extra |
+-------------+------------------------+------+-----+---------+----------------+
| goods_id | smallint(5) unsigned | NO | PRI | NULL | auto_increment |
| goods_name | varchar(150) | NO | | NULL | |
| goods_cate | varchar(40) | NO | | NULL | |
| brand_name | varchar(40) | NO | | NULL | |
| goods_price | decimal(15,3) unsigned | NO | | 0.000 | |
| is_show | tinyint(1) | NO | | 1 | |
| is_saleoff | tinyint(1) | NO | | 0 | |
+-------------+------------------------+------+-----+---------+----------------+
7 rows in set (0.03 sec)
mysql> SHOW COLUMNS FROM tdb_goods_brands;
+------------+----------------------+------+-----+---------+----------------+
| Field | Type | Null | Key | Default | Extra |
+------------+----------------------+------+-----+---------+----------------+
| brand_id | smallint(5) unsigned | NO | PRI | NULL | auto_increment |
| brand_name | varchar(40) | NO | | NULL | |
+------------+----------------------+------+-----+---------+----------------+
2 rows in set (0.00 sec)
mysql> UPDATE tdb_goods AS g INNER JOIN tdb_goods_brands AS b ON g.brand_name=b.brand_name
-> SET g.brand_name=b.brand_id;
Query OK, 22 rows affected (0.06 sec)
Rows matched: 22 Changed: 22 Warnings: 0
mysql> SELECT * FROM tdb_goods\G;
*************************** 1. row ***************************
goods_id: 1
goods_name: R510VC 15.6英寸笔记本
goods_cate: 5
brand_name: 2
goods_price: 3399.000
is_show: 1
is_saleoff: 0
*************************** 2. row ***************************
goods_id: 2
goods_name: Y400N 14.0英寸笔记本电脑
goods_cate: 5
brand_name: 7
goods_price: 4899.000
is_show: 1
is_saleoff: 0
*************************** 3. row ***************************
goods_id: 3
goods_name: G150TH 15.6英寸游戏本
goods_cate: 4
brand_name: 9
goods_price: 8499.000
is_show: 1
is_saleoff: 0
*************************** 4. row ***************************
goods_id: 4
goods_name: X550CC 15.6英寸笔记本
goods_cate: 5
brand_name: 2
goods_price: 2799.000
is_show: 1
is_saleoff: 0
*************************** 5. row ***************************
goods_id: 5
goods_name: X240(20ALA0EYCD) 12.5英寸超极本
goods_cate: 7
brand_name: 7
goods_price: 4999.000
is_show: 1
is_saleoff: 0
*************************** 6. row ***************************
goods_id: 6
goods_name: U330P 13.3英寸超极本
goods_cate: 7
brand_name: 7
goods_price: 4299.000
is_show: 1
is_saleoff: 0
*************************** 7. row ***************************
goods_id: 7
goods_name: SVP13226SCB 13.3英寸触控超极本
goods_cate: 7
brand_name: 6
goods_price: 7999.000
is_show: 1
is_saleoff: 0
*************************** 8. row ***************************
goods_id: 8
goods_name: iPad mini MD531CH/A 7.9英寸平板电脑
goods_cate: 2
brand_name: 8
goods_price: 1998.000
is_show: 1
is_saleoff: 0
*************************** 9. row ***************************
goods_id: 9
goods_name: iPad Air MD788CH/A 9.7英寸平板电脑 (16G WiFi版)
goods_cate: 2
brand_name: 8
goods_price: 3388.000
is_show: 1
is_saleoff: 0
*************************** 10. row ***************************
goods_id: 10
goods_name: iPad mini ME279CH/A 配备 Retina 显示屏 7.9英寸平板电脑 (16G WiFi版)
goods_cate: 2
brand_name: 8
goods_price: 2788.000
is_show: 1
is_saleoff: 0
*************************** 11. row ***************************
goods_id: 11
goods_name: IdeaCentre C340 20英寸一体电脑
goods_cate: 1
brand_name: 7
goods_price: 3499.000
is_show: 1
is_saleoff: 0
*************************** 12. row ***************************
goods_id: 12
goods_name: Vostro 3800-R1206 台式电脑
goods_cate: 1
brand_name: 5
goods_price: 2899.000
is_show: 1
is_saleoff: 0
*************************** 13. row ***************************
goods_id: 13
goods_name: iMac ME086CH/A 21.5英寸一体电脑
goods_cate: 1
brand_name: 8
goods_price: 9188.000
is_show: 1
is_saleoff: 0
*************************** 14. row ***************************
goods_id: 14
goods_name: AT7-7414LP 台式电脑 (i5-3450四核 4G 500G 2G独显 DVD 键鼠 Linux )
goods_cate: 1
brand_name: 3
goods_price: 3699.000
is_show: 1
is_saleoff: 0
*************************** 15. row ***************************
goods_id: 15
goods_name: Z220SFF F4F06PA工作站
goods_cate: 3
brand_name: 4
goods_price: 4288.000
is_show: 1
is_saleoff: 0
*************************** 16. row ***************************
goods_id: 16
goods_name: PowerEdge T110 II服务器
goods_cate: 3
brand_name: 5
goods_price: 5388.000
is_show: 1
is_saleoff: 0
*************************** 17. row ***************************
goods_id: 17
goods_name: Mac Pro MD878CH/A 专业级台式电脑
goods_cate: 3
brand_name: 8
goods_price: 28888.000
is_show: 1
is_saleoff: 0
*************************** 18. row ***************************
goods_id: 18
goods_name: HMZ-T3W 头戴显示设备
goods_cate: 6
brand_name: 6
goods_price: 6999.000
is_show: 1
is_saleoff: 0
*************************** 19. row ***************************
goods_id: 19
goods_name: 商务双肩背包
goods_cate: 6
brand_name: 6
goods_price: 99.000
is_show: 1
is_saleoff: 0
*************************** 20. row ***************************
goods_id: 20
goods_name: X3250 M4机架式服务器 2583i14
goods_cate: 3
brand_name: 1
goods_price: 6888.000
is_show: 1
is_saleoff: 0
*************************** 21. row ***************************
goods_id: 21
goods_name: HMZ-T3W 头戴显示设备
goods_cate: 6
brand_name: 6
goods_price: 6999.000
is_show: 1
is_saleoff: 0
*************************** 22. row ***************************
goods_id: 22
goods_name: 商务双肩背包
goods_cate: 6
brand_name: 6
goods_price: 99.000
is_show: 1
is_saleoff: 0
22 rows in set (0.00 sec)
ERROR:
No query specified
mysql> SHOW COLUMNS FROM tdb_goods;
+-------------+------------------------+------+-----+---------+----------------+
| Field | Type | Null | Key | Default | Extra |
+-------------+------------------------+------+-----+---------+----------------+
| goods_id | smallint(5) unsigned | NO | PRI | NULL | auto_increment |
| goods_name | varchar(150) | NO | | NULL | |
| goods_cate | varchar(40) | NO | | NULL | |
| brand_name | varchar(40) | NO | | NULL | |
| goods_price | decimal(15,3) unsigned | NO | | 0.000 | |
| is_show | tinyint(1) | NO | | 1 | |
| is_saleoff | tinyint(1) | NO | | 0 | |
+-------------+------------------------+------+-----+---------+----------------+
7 rows in set (0.00 sec)
mysql> ALTER TABLE tdb_goods
-> CHANGE goods_cate cate_id SMALLINT UNSIGNED NOT NULL,
-> CHANGE brand_name brand_id SMALLINT UNSIGNED NOT NULL;
Query OK, 22 rows affected (0.67 sec)
Records: 22 Duplicates: 0 Warnings: 0
mysql> SHOW COLUMNS FROM tdb_goods;
+-------------+------------------------+------+-----+---------+----------------+
| Field | Type | Null | Key | Default | Extra |
+-------------+------------------------+------+-----+---------+----------------+
| goods_id | smallint(5) unsigned | NO | PRI | NULL | auto_increment |
| goods_name | varchar(150) | NO | | NULL | |
| cate_id | smallint(5) unsigned | NO | | NULL | |
| brand_id | smallint(5) unsigned | NO | | NULL | |
| goods_price | decimal(15,3) unsigned | NO | | 0.000 | |
| is_show | tinyint(1) | NO | | 1 | |
| is_saleoff | tinyint(1) | NO | | 0 | |
+-------------+------------------------+------+-----+---------+----------------+
7 rows in set (0.00 sec)
mysql> #创建一个事实的外键;
mysql> SELECT * FROM tdb_goods\G;
*************************** 1. row ***************************
goods_id: 1
goods_name: R510VC 15.6英寸笔记本
cate_id: 5
brand_id: 2
goods_price: 3399.000
is_show: 1
is_saleoff: 0
*************************** 2. row ***************************
goods_id: 2
goods_name: Y400N 14.0英寸笔记本电脑
cate_id: 5
brand_id: 7
goods_price: 4899.000
is_show: 1
is_saleoff: 0
*************************** 3. row ***************************
goods_id: 3
goods_name: G150TH 15.6英寸游戏本
cate_id: 4
brand_id: 9
goods_price: 8499.000
is_show: 1
is_saleoff: 0
*************************** 4. row ***************************
goods_id: 4
goods_name: X550CC 15.6英寸笔记本
cate_id: 5
brand_id: 2
goods_price: 2799.000
is_show: 1
is_saleoff: 0
*************************** 5. row ***************************
goods_id: 5
goods_name: X240(20ALA0EYCD) 12.5英寸超极本
cate_id: 7
brand_id: 7
goods_price: 4999.000
is_show: 1
is_saleoff: 0
*************************** 6. row ***************************
goods_id: 6
goods_name: U330P 13.3英寸超极本
cate_id: 7
brand_id: 7
goods_price: 4299.000
is_show: 1
is_saleoff: 0
*************************** 7. row ***************************
goods_id: 7
goods_name: SVP13226SCB 13.3英寸触控超极本
cate_id: 7
brand_id: 6
goods_price: 7999.000
is_show: 1
is_saleoff: 0
*************************** 8. row ***************************
goods_id: 8
goods_name: iPad mini MD531CH/A 7.9英寸平板电脑
cate_id: 2
brand_id: 8
goods_price: 1998.000
is_show: 1
is_saleoff: 0
*************************** 9. row ***************************
goods_id: 9
goods_name: iPad Air MD788CH/A 9.7英寸平板电脑 (16G WiFi版)
cate_id: 2
brand_id: 8
goods_price: 3388.000
is_show: 1
is_saleoff: 0
*************************** 10. row ***************************
goods_id: 10
goods_name: iPad mini ME279CH/A 配备 Retina 显示屏 7.9英寸平板电脑 (16G WiFi版)
cate_id: 2
brand_id: 8
goods_price: 2788.000
is_show: 1
is_saleoff: 0
*************************** 11. row ***************************
goods_id: 11
goods_name: IdeaCentre C340 20英寸一体电脑
cate_id: 1
brand_id: 7
goods_price: 3499.000
is_show: 1
is_saleoff: 0
*************************** 12. row ***************************
goods_id: 12
goods_name: Vostro 3800-R1206 台式电脑
cate_id: 1
brand_id: 5
goods_price: 2899.000
is_show: 1
is_saleoff: 0
*************************** 13. row ***************************
goods_id: 13
goods_name: iMac ME086CH/A 21.5英寸一体电脑
cate_id: 1
brand_id: 8
goods_price: 9188.000
is_show: 1
is_saleoff: 0
*************************** 14. row ***************************
goods_id: 14
goods_name: AT7-7414LP 台式电脑 (i5-3450四核 4G 500G 2G独显 DVD 键鼠 Linux )
cate_id: 1
brand_id: 3
goods_price: 3699.000
is_show: 1
is_saleoff: 0
*************************** 15. row ***************************
goods_id: 15
goods_name: Z220SFF F4F06PA工作站
cate_id: 3
brand_id: 4
goods_price: 4288.000
is_show: 1
is_saleoff: 0
*************************** 16. row ***************************
goods_id: 16
goods_name: PowerEdge T110 II服务器
cate_id: 3
brand_id: 5
goods_price: 5388.000
is_show: 1
is_saleoff: 0
*************************** 17. row ***************************
goods_id: 17
goods_name: Mac Pro MD878CH/A 专业级台式电脑
cate_id: 3
brand_id: 8
goods_price: 28888.000
is_show: 1
is_saleoff: 0
*************************** 18. row ***************************
goods_id: 18
goods_name: HMZ-T3W 头戴显示设备
cate_id: 6
brand_id: 6
goods_price: 6999.000
is_show: 1
is_saleoff: 0
*************************** 19. row ***************************
goods_id: 19
goods_name: 商务双肩背包
cate_id: 6
brand_id: 6
goods_price: 99.000
is_show: 1
is_saleoff: 0
*************************** 20. row ***************************
goods_id: 20
goods_name: X3250 M4机架式服务器 2583i14
cate_id: 3
brand_id: 1
goods_price: 6888.000
is_show: 1
is_saleoff: 0
*************************** 21. row ***************************
goods_id: 21
goods_name: HMZ-T3W 头戴显示设备
cate_id: 6
brand_id: 6
goods_price: 6999.000
is_show: 1
is_saleoff: 0
*************************** 22. row ***************************
goods_id: 22
goods_name: 商务双肩背包
cate_id: 6
brand_id: 6
goods_price: 99.000
is_show: 1
is_saleoff: 0
22 rows in set (0.00 sec)
ERROR:
No query specified
mysql> INSERT tdb_goods_cates(cate_name) VALUES('路由器'),('交换机'),('网卡');
ERROR 1146 (42S02): Table 'world.tdb_goods_cates' doesn't exist
mysql>
mysql> INSERT tdb_goods_brands(brand_name) VALUES('海尔'),('清华同方'),('神舟');
Query OK, 3 rows affected (0.07 sec)
Records: 3 Duplicates: 0 Warnings: 0
mysql> #在tdb_goods数据表写入任意记录
mysql> INSERT tdb_goods(goods_name,cate_id,brand_id,goods_price)
VALUES(' LaserJet Pro P1606dn 黑白激光打印机','12','4','1849');
Query OK, 1 row affected (0.08 sec)
mysql> SELECT * FROM tdb_goods_cate;
+---------+---------------+
| cate_id | cate_name |
+---------+---------------+
| 1 | 台式机 |
| 2 | 平板电脑 |
| 3 | 服务器/工作站 |
| 4 | 游戏本 |
| 5 | 笔记本 |
| 6 | 笔记本配件 |
| 7 | 超级本 |
+---------+---------------+
7 rows in set (0.03 sec)
mysql> SELECT * FROM tdb_goods\G;
*************************** 1. row ***************************
goods_id: 1
goods_name: R510VC 15.6英寸笔记本
cate_id: 5
brand_id: 2
goods_price: 3399.000
is_show: 1
is_saleoff: 0
*************************** 2. row ***************************
goods_id: 2
goods_name: Y400N 14.0英寸笔记本电脑
cate_id: 5
brand_id: 7
goods_price: 4899.000
is_show: 1
is_saleoff: 0
*************************** 3. row ***************************
goods_id: 3
goods_name: G150TH 15.6英寸游戏本
cate_id: 4
brand_id: 9
goods_price: 8499.000
is_show: 1
is_saleoff: 0
*************************** 4. row ***************************
goods_id: 4
goods_name: X550CC 15.6英寸笔记本
cate_id: 5
brand_id: 2
goods_price: 2799.000
is_show: 1
is_saleoff: 0
*************************** 5. row ***************************
goods_id: 5
goods_name: X240(20ALA0EYCD) 12.5英寸超极本
cate_id: 7
brand_id: 7
goods_price: 4999.000
is_show: 1
is_saleoff: 0
*************************** 6. row ***************************
goods_id: 6
goods_name: U330P 13.3英寸超极本
cate_id: 7
brand_id: 7
goods_price: 4299.000
is_show: 1
is_saleoff: 0
*************************** 7. row ***************************
goods_id: 7
goods_name: SVP13226SCB 13.3英寸触控超极本
cate_id: 7
brand_id: 6
goods_price: 7999.000
is_show: 1
is_saleoff: 0
*************************** 8. row ***************************
goods_id: 8
goods_name: iPad mini MD531CH/A 7.9英寸平板电脑
cate_id: 2
brand_id: 8
goods_price: 1998.000
is_show: 1
is_saleoff: 0
*************************** 9. row ***************************
goods_id: 9
goods_name: iPad Air MD788CH/A 9.7英寸平板电脑 (16G WiFi版)
cate_id: 2
brand_id: 8
goods_price: 3388.000
is_show: 1
is_saleoff: 0
*************************** 10. row ***************************
goods_id: 10
goods_name: iPad mini ME279CH/A 配备 Retina 显示屏 7.9英寸平板电脑 (16G WiFi版)
cate_id: 2
brand_id: 8
goods_price: 2788.000
is_show: 1
is_saleoff: 0
*************************** 11. row ***************************
goods_id: 11
goods_name: IdeaCentre C340 20英寸一体电脑
cate_id: 1
brand_id: 7
goods_price: 3499.000
is_show: 1
is_saleoff: 0
*************************** 12. row ***************************
goods_id: 12
goods_name: Vostro 3800-R1206 台式电脑
cate_id: 1
brand_id: 5
goods_price: 2899.000
is_show: 1
is_saleoff: 0
*************************** 13. row ***************************
goods_id: 13
goods_name: iMac ME086CH/A 21.5英寸一体电脑
cate_id: 1
brand_id: 8
goods_price: 9188.000
is_show: 1
is_saleoff: 0
*************************** 14. row ***************************
goods_id: 14
goods_name: AT7-7414LP 台式电脑 (i5-3450四核 4G 500G 2G独显 DVD 键鼠 Linux )
cate_id: 1
brand_id: 3
goods_price: 3699.000
is_show: 1
is_saleoff: 0
*************************** 15. row ***************************
goods_id: 15
goods_name: Z220SFF F4F06PA工作站
cate_id: 3
brand_id: 4
goods_price: 4288.000
is_show: 1
is_saleoff: 0
*************************** 16. row ***************************
goods_id: 16
goods_name: PowerEdge T110 II服务器
cate_id: 3
brand_id: 5
goods_price: 5388.000
is_show: 1
is_saleoff: 0
*************************** 17. row ***************************
goods_id: 17
goods_name: Mac Pro MD878CH/A 专业级台式电脑
cate_id: 3
brand_id: 8
goods_price: 28888.000
is_show: 1
is_saleoff: 0
*************************** 18. row ***************************
goods_id: 18
goods_name: HMZ-T3W 头戴显示设备
cate_id: 6
brand_id: 6
goods_price: 6999.000
is_show: 1
is_saleoff: 0
*************************** 19. row ***************************
goods_id: 19
goods_name: 商务双肩背包
cate_id: 6
brand_id: 6
goods_price: 99.000
is_show: 1
is_saleoff: 0
*************************** 20. row ***************************
goods_id: 20
goods_name: X3250 M4机架式服务器 2583i14
cate_id: 3
brand_id: 1
goods_price: 6888.000
is_show: 1
is_saleoff: 0
*************************** 21. row ***************************
goods_id: 21
goods_name: HMZ-T3W 头戴显示设备
cate_id: 6
brand_id: 6
goods_price: 6999.000
is_show: 1
is_saleoff: 0
*************************** 22. row ***************************
goods_id: 22
goods_name: 商务双肩背包
cate_id: 6
brand_id: 6
goods_price: 99.000
is_show: 1
is_saleoff: 0
*************************** 23. row ***************************
goods_id: 23
goods_name: LaserJet Pro P1606dn 黑白激光打印机
cate_id: 12
brand_id: 4
goods_price: 1849.000
is_show: 1
is_saleoff: 0
23 rows in set (0.00 sec)
ERROR:
No query specified
mysql> #数据表参照,用别名;
mysql> #内链接 ,取交集;
mysql> SHOW COLUMNS FROM tdb_goods;
+-------------+------------------------+------+-----+---------+----------------+
| Field | Type | Null | Key | Default | Extra |
+-------------+------------------------+------+-----+---------+----------------+
| goods_id | smallint(5) unsigned | NO | PRI | NULL | auto_increment |
| goods_name | varchar(150) | NO | | NULL | |
| cate_id | smallint(5) unsigned | NO | | NULL | |
| brand_id | smallint(5) unsigned | NO | | NULL | |
| goods_price | decimal(15,3) unsigned | NO | | 0.000 | |
| is_show | tinyint(1) | NO | | 1 | |
| is_saleoff | tinyint(1) | NO | | 0 | |
+-------------+------------------------+------+-----+---------+----------------+
7 rows in set (0.00 sec)
mysql> SHOW COLUMNS FROM tdb_goods_cate;
+-----------+----------------------+------+-----+---------+----------------+
| Field | Type | Null | Key | Default | Extra |
+-----------+----------------------+------+-----+---------+----------------+
| cate_id | smallint(5) unsigned | NO | PRI | NULL | auto_increment |
| cate_name | varchar(40) | NO | | NULL | |
+-----------+----------------------+------+-----+---------+----------------+
2 rows in set (0.00 sec)
mysql> SELECT goods_id,goods_name,cate_name
-> FROM tdb_goods INNER JOIN tdb_goods_cate
-> ON tdb_goods.cate_id=tdb_goods_cate.cate_id;
+----------+------------------------------------------------------------------------+---------------+
| goods_id | goods_name | cate_name |
+----------+------------------------------------------------------------------------+---------------+
| 1 | R510VC 15.6英寸笔记本 | 笔记本 |
| 2 | Y400N 14.0英寸笔记本电脑 | 笔记本 |
| 3 | G150TH 15.6英寸游戏本 | 游戏本 |
| 4 | X550CC 15.6英寸笔记本 | 笔记本 |
| 5 | X240(20ALA0EYCD) 12.5英寸超极本 | 超级本 |
| 6 | U330P 13.3英寸超极本 | 超级本 |
| 7 | SVP13226SCB 13.3英寸触控超极本 | 超级本 |
| 8 | iPad mini MD531CH/A 7.9英寸平板电脑 | 平板电脑 |
| 9 | iPad Air MD788CH/A 9.7英寸平板电脑 (16G WiFi版) | 平板电脑 |
| 10 | iPad mini ME279CH/A 配备 Retina 显示屏 7.9英寸平板电脑 (16G WiFi版) | 平板电脑 |
| 11 | IdeaCentre C340 20英寸一体电脑 | 台式机 |
| 12 | Vostro 3800-R1206 台式电脑 | 台式机 |
| 13 | iMac ME086CH/A 21.5英寸一体电脑 | 台式机 |
| 14 | AT7-7414LP 台式电脑 (i5-3450四核 4G 500G 2G独显 DVD 键鼠 Linux ) | 台式机 |
| 15 | Z220SFF F4F06PA工作站 | 服务器/工作站 |
| 16 | PowerEdge T110 II服务器 | 服务器/工作站 |
| 17 | Mac Pro MD878CH/A 专业级台式电脑 | 服务器/工作站 |
| 18 | HMZ-T3W 头戴显示设备 | 笔记本配件 |
| 19 | 商务双肩背包 | 笔记本配件 |
| 20 | X3250 M4机架式服务器 2583i14 | 服务器/工作站 |
| 21 | HMZ-T3W 头戴显示设备 | 笔记本配件 |
| 22 | 商务双肩背包 | 笔记本配件 |
+----------+------------------------------------------------------------------------+---------------+
22 rows in set (0.01 sec)
mysql> SELECT * FROM tdb_goods_cate;
+---------+---------------+
| cate_id | cate_name |
+---------+---------------+
| 1 | 台式机 |
| 2 | 平板电脑 |
| 3 | 服务器/工作站 |
| 4 | 游戏本 |
| 5 | 笔记本 |
| 6 | 笔记本配件 |
| 7 | 超级本 |
+---------+---------------+
7 rows in set (0.00 sec)
mysql> #左外连接,取左表中的全部和右表符合条件的部分;
mysql> SELECT goods_id,goods_name,cate_name
-> FROM tdb_goods LEFT JOIN tdb_goods_cate
-> ON tdb_goods.cate_id=tdb_goods_cate.cate_id;
+----------+------------------------------------------------------------------------+---------------+
| goods_id | goods_name | cate_name |
+----------+------------------------------------------------------------------------+---------------+
| 1 | R510VC 15.6英寸笔记本 | 笔记本 |
| 2 | Y400N 14.0英寸笔记本电脑 | 笔记本 |
| 3 | G150TH 15.6英寸游戏本 | 游戏本 |
| 4 | X550CC 15.6英寸笔记本 | 笔记本 |
| 5 | X240(20ALA0EYCD) 12.5英寸超极本 | 超级本 |
| 6 | U330P 13.3英寸超极本 | 超级本 |
| 7 | SVP13226SCB 13.3英寸触控超极本 | 超级本 |
| 8 | iPad mini MD531CH/A 7.9英寸平板电脑 | 平板电脑 |
| 9 | iPad Air MD788CH/A 9.7英寸平板电脑 (16G WiFi版) | 平板电脑 |
| 10 | iPad mini ME279CH/A 配备 Retina 显示屏 7.9英寸平板电脑 (16G WiFi版) | 平板电脑 |
| 11 | IdeaCentre C340 20英寸一体电脑 | 台式机 |
| 12 | Vostro 3800-R1206 台式电脑 | 台式机 |
| 13 | iMac ME086CH/A 21.5英寸一体电脑 | 台式机 |
| 14 | AT7-7414LP 台式电脑 (i5-3450四核 4G 500G 2G独显 DVD 键鼠 Linux ) | 台式机 |
| 15 | Z220SFF F4F06PA工作站 | 服务器/工作站 |
| 16 | PowerEdge T110 II服务器 | 服务器/工作站 |
| 17 | Mac Pro MD878CH/A 专业级台式电脑 | 服务器/工作站 |
| 18 | HMZ-T3W 头戴显示设备 | 笔记本配件 |
| 19 | 商务双肩背包 | 笔记本配件 |
| 20 | X3250 M4机架式服务器 2583i14 | 服务器/工作站 |
| 21 | HMZ-T3W 头戴显示设备 | 笔记本配件 |
| 22 | 商务双肩背包 | 笔记本配件 |
| 23 | LaserJet Pro P1606dn 黑白激光打印机 | NULL |
+----------+------------------------------------------------------------------------+---------------+
23 rows in set (0.00 sec)
mysql> #右外连接,取右表中的全部和左表符合条件的部分;
mysql> SELECT goods_id,goods_name,cate_name
-> FROM tdb_goods RIGHT JOIN tdb_goods_cate
-> ON tdb_goods.cate_id=tdb_goods_cate.cate_id;
+----------+------------------------------------------------------------------------+---------------+
| goods_id | goods_name | cate_name |
+----------+------------------------------------------------------------------------+---------------+
| 1 | R510VC 15.6英寸笔记本 | 笔记本 |
| 2 | Y400N 14.0英寸笔记本电脑 | 笔记本 |
| 3 | G150TH 15.6英寸游戏本 | 游戏本 |
| 4 | X550CC 15.6英寸笔记本 | 笔记本 |
| 5 | X240(20ALA0EYCD) 12.5英寸超极本 | 超级本 |
| 6 | U330P 13.3英寸超极本 | 超级本 |
| 7 | SVP13226SCB 13.3英寸触控超极本 | 超级本 |
| 8 | iPad mini MD531CH/A 7.9英寸平板电脑 | 平板电脑 |
| 9 | iPad Air MD788CH/A 9.7英寸平板电脑 (16G WiFi版) | 平板电脑 |
| 10 | iPad mini ME279CH/A 配备 Retina 显示屏 7.9英寸平板电脑 (16G WiFi版) | 平板电脑 |
| 11 | IdeaCentre C340 20英寸一体电脑 | 台式机 |
| 12 | Vostro 3800-R1206 台式电脑 | 台式机 |
| 13 | iMac ME086CH/A 21.5英寸一体电脑 | 台式机 |
| 14 | AT7-7414LP 台式电脑 (i5-3450四核 4G 500G 2G独显 DVD 键鼠 Linux ) | 台式机 |
| 15 | Z220SFF F4F06PA工作站 | 服务器/工作站 |
| 16 | PowerEdge T110 II服务器 | 服务器/工作站 |
| 17 | Mac Pro MD878CH/A 专业级台式电脑 | 服务器/工作站 |
| 18 | HMZ-T3W 头戴显示设备 | 笔记本配件 |
| 19 | 商务双肩背包 | 笔记本配件 |
| 20 | X3250 M4机架式服务器 2583i14 | 服务器/工作站 |
| 21 | HMZ-T3W 头戴显示设备 | 笔记本配件 |
| 22 | 商务双肩背包 | 笔记本配件 |
+----------+------------------------------------------------------------------------+---------------+
22 rows in set (0.02 sec)
mysql> SELECT goods_id,goods_name,cate_name
-> FROM tdb_goods LEFT JOIN tdb_goods_cate
-> ON tdb_goods.cate_id=tdb_goods_cate.cate_id\G;
*************************** 1. row ***************************
goods_id: 1
goods_name: R510VC 15.6英寸笔记本
cate_name: 笔记本
*************************** 2. row ***************************
goods_id: 2
goods_name: Y400N 14.0英寸笔记本电脑
cate_name: 笔记本
*************************** 3. row ***************************
goods_id: 3
goods_name: G150TH 15.6英寸游戏本
cate_name: 游戏本
*************************** 4. row ***************************
goods_id: 4
goods_name: X550CC 15.6英寸笔记本
cate_name: 笔记本
*************************** 5. row ***************************
goods_id: 5
goods_name: X240(20ALA0EYCD) 12.5英寸超极本
cate_name: 超级本
*************************** 6. row ***************************
goods_id: 6
goods_name: U330P 13.3英寸超极本
cate_name: 超级本
*************************** 7. row ***************************
goods_id: 7
goods_name: SVP13226SCB 13.3英寸触控超极本
cate_name: 超级本
*************************** 8. row ***************************
goods_id: 8
goods_name: iPad mini MD531CH/A 7.9英寸平板电脑
cate_name: 平板电脑
*************************** 9. row ***************************
goods_id: 9
goods_name: iPad Air MD788CH/A 9.7英寸平板电脑 (16G WiFi版)
cate_name: 平板电脑
*************************** 10. row ***************************
goods_id: 10
goods_name: iPad mini ME279CH/A 配备 Retina 显示屏 7.9英寸平板电脑 (16G WiFi版)
cate_name: 平板电脑
*************************** 11. row ***************************
goods_id: 11
goods_name: IdeaCentre C340 20英寸一体电脑
cate_name: 台式机
*************************** 12. row ***************************
goods_id: 12
goods_name: Vostro 3800-R1206 台式电脑
cate_name: 台式机
*************************** 13. row ***************************
goods_id: 13
goods_name: iMac ME086CH/A 21.5英寸一体电脑
cate_name: 台式机
*************************** 14. row ***************************
goods_id: 14
goods_name: AT7-7414LP 台式电脑 (i5-3450四核 4G 500G 2G独显 DVD 键鼠 Linux )
cate_name: 台式机
*************************** 15. row ***************************
goods_id: 15
goods_name: Z220SFF F4F06PA工作站
cate_name: 服务器/工作站
*************************** 16. row ***************************
goods_id: 16
goods_name: PowerEdge T110 II服务器
cate_name: 服务器/工作站
*************************** 17. row ***************************
goods_id: 17
goods_name: Mac Pro MD878CH/A 专业级台式电脑
cate_name: 服务器/工作站
*************************** 18. row ***************************
goods_id: 18
goods_name: HMZ-T3W 头戴显示设备
cate_name: 笔记本配件
*************************** 19. row ***************************
goods_id: 19
goods_name: 商务双肩背包
cate_name: 笔记本配件
*************************** 20. row ***************************
goods_id: 20
goods_name: X3250 M4机架式服务器 2583i14
cate_name: 服务器/工作站
*************************** 21. row ***************************
goods_id: 21
goods_name: HMZ-T3W 头戴显示设备
cate_name: 笔记本配件
*************************** 22. row ***************************
goods_id: 22
goods_name: 商务双肩背包
cate_name: 笔记本配件
*************************** 23. row ***************************
goods_id: 23
goods_name: LaserJet Pro P1606dn 黑白激光打印机
cate_name: NULL
23 rows in set (0.00 sec)
ERROR:
No query specified
mysql> #多表连接;
mysql> SHOW COLUMNS FROM tdb_goods\G;
*************************** 1. row ***************************
Field: goods_id
Type: smallint(5) unsigned
Null: NO
Key: PRI
Default: NULL
Extra: auto_increment
*************************** 2. row ***************************
Field: goods_name
Type: varchar(150)
Null: NO
Key:
Default: NULL
Extra:
*************************** 3. row ***************************
Field: cate_id
Type: smallint(5) unsigned
Null: NO
Key:
Default: NULL
Extra:
*************************** 4. row ***************************
Field: brand_id
Type: smallint(5) unsigned
Null: NO
Key:
Default: NULL
Extra:
*************************** 5. row ***************************
Field: goods_price
Type: decimal(15,3) unsigned
Null: NO
Key:
Default: 0.000
Extra:
*************************** 6. row ***************************
Field: is_show
Type: tinyint(1)
Null: NO
Key:
Default: 1
Extra:
*************************** 7. row ***************************
Field: is_saleoff
Type: tinyint(1)
Null: NO
Key:
Default: 0
Extra:
7 rows in set (0.00 sec)
ERROR:
No query specified
mysql> #实现三张表的连接;
mysql> SELECT goods_id,goods_name,cate_name,brand_name,goods_price FROM tdb_goods AS g
-> INNER JOIN tdb_goods_cate AS c
-> ON g.cate_id=c.cate_id
-> INNER JOIN tdb_goods_brands AS b
-> ON g.brand_id=b.brand_id\G;
*************************** 1. row ***************************
goods_id: 1
goods_name: R510VC 15.6英寸笔记本
cate_name: 笔记本
brand_name: 华硕
goods_price: 3399.000
*************************** 2. row ***************************
goods_id: 2
goods_name: Y400N 14.0英寸笔记本电脑
cate_name: 笔记本
brand_name: 联想
goods_price: 4899.000
*************************** 3. row ***************************
goods_id: 3
goods_name: G150TH 15.6英寸游戏本
cate_name: 游戏本
brand_name: 雷神
goods_price: 8499.000
*************************** 4. row ***************************
goods_id: 4
goods_name: X550CC 15.6英寸笔记本
cate_name: 笔记本
brand_name: 华硕
goods_price: 2799.000
*************************** 5. row ***************************
goods_id: 5
goods_name: X240(20ALA0EYCD) 12.5英寸超极本
cate_name: 超级本
brand_name: 联想
goods_price: 4999.000
*************************** 6. row ***************************
goods_id: 6
goods_name: U330P 13.3英寸超极本
cate_name: 超级本
brand_name: 联想
goods_price: 4299.000
*************************** 7. row ***************************
goods_id: 7
goods_name: SVP13226SCB 13.3英寸触控超极本
cate_name: 超级本
brand_name: 索尼
goods_price: 7999.000
*************************** 8. row ***************************
goods_id: 8
goods_name: iPad mini MD531CH/A 7.9英寸平板电脑
cate_name: 平板电脑
brand_name: 苹果
goods_price: 1998.000
*************************** 9. row ***************************
goods_id: 9
goods_name: iPad Air MD788CH/A 9.7英寸平板电脑 (16G WiFi版)
cate_name: 平板电脑
brand_name: 苹果
goods_price: 3388.000
*************************** 10. row ***************************
goods_id: 10
goods_name: iPad mini ME279CH/A 配备 Retina 显示屏 7.9英寸平板电脑 (16G WiFi版)
cate_name: 平板电脑
brand_name: 苹果
goods_price: 2788.000
*************************** 11. row ***************************
goods_id: 11
goods_name: IdeaCentre C340 20英寸一体电脑
cate_name: 台式机
brand_name: 联想
goods_price: 3499.000
*************************** 12. row ***************************
goods_id: 12
goods_name: Vostro 3800-R1206 台式电脑
cate_name: 台式机
brand_name: 戴尔
goods_price: 2899.000
*************************** 13. row ***************************
goods_id: 13
goods_name: iMac ME086CH/A 21.5英寸一体电脑
cate_name: 台式机
brand_name: 苹果
goods_price: 9188.000
*************************** 14. row ***************************
goods_id: 14
goods_name: AT7-7414LP 台式电脑 (i5-3450四核 4G 500G 2G独显 DVD 键鼠 Linux )
cate_name: 台式机
brand_name: 宏碁
goods_price: 3699.000
*************************** 15. row ***************************
goods_id: 15
goods_name: Z220SFF F4F06PA工作站
cate_name: 服务器/工作站
brand_name: 惠普
goods_price: 4288.000
*************************** 16. row ***************************
goods_id: 16
goods_name: PowerEdge T110 II服务器
cate_name: 服务器/工作站
brand_name: 戴尔
goods_price: 5388.000
*************************** 17. row ***************************
goods_id: 17
goods_name: Mac Pro MD878CH/A 专业级台式电脑
cate_name: 服务器/工作站
brand_name: 苹果
goods_price: 28888.000
*************************** 18. row ***************************
goods_id: 18
goods_name: HMZ-T3W 头戴显示设备
cate_name: 笔记本配件
brand_name: 索尼
goods_price: 6999.000
*************************** 19. row ***************************
goods_id: 19
goods_name: 商务双肩背包
cate_name: 笔记本配件
brand_name: 索尼
goods_price: 99.000
*************************** 20. row ***************************
goods_id: 20
goods_name: X3250 M4机架式服务器 2583i14
cate_name: 服务器/工作站
brand_name: IBM
goods_price: 6888.000
*************************** 21. row ***************************
goods_id: 21
goods_name: HMZ-T3W 头戴显示设备
cate_name: 笔记本配件
brand_name: 索尼
goods_price: 6999.000
*************************** 22. row ***************************
goods_id: 22
goods_name: 商务双肩背包
cate_name: 笔记本配件
brand_name: 索尼
goods_price: 99.000
22 rows in set (0.02 sec)
ERROR:
No query specified
mysql>
mysql> #SHOW COLUMNS FROM tdb_goods_cate;
mysql> SHOW COLUMNS FROM tdb_goods_cate;
+-----------+----------------------+------+-----+---------+----------------+
| Field | Type | Null | Key | Default | Extra |
+-----------+----------------------+------+-----+---------+----------------+
| cate_id | smallint(5) unsigned | NO | PRI | NULL | auto_increment |
| cate_name | varchar(40) | NO | | NULL | |
+-----------+----------------------+------+-----+---------+----------------+
2 rows in set (0.00 sec)
mysql> SELECT * FROM tdb_goods_cate;
+---------+---------------+
| cate_id | cate_name |
+---------+---------------+
| 1 | 台式机 |
| 2 | 平板电脑 |
| 3 | 服务器/工作站 |
| 4 | 游戏本 |
| 5 | 笔记本 |
| 6 | 笔记本配件 |
| 7 | 超级本 |
+---------+---------------+
7 rows in set (0.00 sec)
mysql> CREATE TABLE tdb_goods_types(
-> type_id SMALLINT UNSIGNED PRIMARY KEY AUTO_INCREMENT,
-> type_name VARCHAR(20) NOT NULL,
-> parent_id SMALLINT UNSIGNED NOT NULL DEFAULT 0
-> );
Query OK, 0 rows affected (0.19 sec)
mysql> INSERT tdb_goods_types(type_name,parent_id) VALUES('家用电器',DEFAULT);
Query OK, 1 row affected (0.05 sec)
mysql> INSERT tdb_goods_types(type_name,parent_id) VALUES('电脑、办公',DEFAULT);
Query OK, 1 row affected (0.02 sec)
mysql> INSERT tdb_goods_types(type_name,parent_id) VALUES('大家电',1);
Query OK, 1 row affected (0.06 sec)
mysql> INSERT tdb_goods_types(type_name,parent_id) VALUES('生活电器',1);
Query OK, 1 row affected (0.05 sec)
mysql> INSERT tdb_goods_types(type_name,parent_id) VALUES('平板电视',3);
Query OK, 1 row affected (0.02 sec)
mysql> INSERT tdb_goods_types(type_name,parent_id) VALUES('空调',3);
Query OK, 1 row affected (0.02 sec)
mysql> INSERT tdb_goods_types(type_name,parent_id) VALUES('电风扇',4);
Query OK, 1 row affected (0.02 sec)
mysql> INSERT tdb_goods_types(ty