MariaDB刪除數(shù)據(jù)

MariaDB DELETE語(yǔ)句用于從MariaDB數(shù)據(jù)庫(kù)的表中刪除一個(gè)或多個(gè)記錄。

語(yǔ)法：

DELETE FROM table  
[WHERE conditions]  
[ORDER BY expression [ ASC | DESC ]]  
[LIMIT number_rows];

1. 使用條件刪除數(shù)據(jù)

下面演示如何使用指定的一個(gè)條件來(lái)刪除數(shù)據(jù)。

示例：

DELETE FROM Students  
WHERE student_name = 'Blaba';

在執(zhí)行上面刪除語(yǔ)句后，現(xiàn)在查詢表中的數(shù)據(jù) -

2. 使用多個(gè)條件刪除數(shù)據(jù)

假設(shè)數(shù)據(jù)庫(kù)表students中的student_name有兩個(gè)Maxsu值，現(xiàn)在想刪除student_id不是1的所有Maxsu值，參考以下語(yǔ)句 -

首先插入兩條件記錄 -

INSERT INTO Students  
(student_name, student_address, admission_date) 
VALUES('Maxsu','Sanya','2016-03-09 00:00:00');
-- 再插入另一條記錄
INSERT INTO Students  
(student_name, student_address, admission_date) 
VALUES('Ajeet','Sanya','2015-12-07 00:00:00');

查詢當(dāng)數(shù)據(jù)庫(kù)中的記錄 -

MariaDB [testdb]> select * from students;
+------------+--------------+-----------------+----------------+
| student_id | student_name | student_address | admission_date |
+------------+--------------+-----------------+----------------+
|          1 | Maxsu        | Haikou          | 2017-01-07     |
|          3 | JMaster      | Beijing         | 2016-05-07     |
|          4 | Mahesh       | Guangzhou       | 2016-06-07     |
|          5 | 科比         | Haikou          | 2016-02-07     |
|          7 | Maxsu        | Sanya           | 2016-03-09     |
|          8 | Ajeet        | Sanya           | 2015-12-07     |
+------------+--------------+-----------------+----------------+
6 rows in set (0.00 sec)

刪除那些student_id大于1，并且student_name為Maxsu的記錄 -

DELETE FROM Students
WHERE student_name = 'Maxsu'
AND student_id > 1;

執(zhí)行上面刪除語(yǔ)句以后，現(xiàn)在查詢表中的記錄 -

MariaDB [testdb]> select * from students;
+------------+--------------+-----------------+----------------+
| student_id | student_name | student_address | admission_date |
+------------+--------------+-----------------+----------------+
|          1 | Maxsu        | Haikou          | 2017-01-07     |
|          3 | JMaster      | Beijing         | 2016-05-07     |
|          4 | Mahesh       | Guangzhou       | 2016-06-07     |
|          5 | 科比         | Haikou          | 2016-02-07     |
|          8 | Ajeet        | Sanya           | 2015-12-07     |
+------------+--------------+-----------------+----------------+
5 rows in set (0.00 sec)

可以看到，student_id為7，并且student_name值為Maxsu的記錄被刪除了。