INSERT & DELETE & UPDATA

INSERT

INSERT [LOW_PRIORITY | DELAYED | HIGH_PRIORITY] [IGNORE]
[INTO] tbl_name [(col_name,...)]
{VALUES | VALUE} ({expr | DEFAULT},...),(...),...
[ ON DUPLICATE KEY UPDATE
col_name=expr
[, col_name=expr] ... ]

Or:

INSERT [LOW_PRIORITY | DELAYED | HIGH_PRIORITY] [IGNORE]
[INTO] tbl_name
SET col_name={expr | DEFAULT}, ...
[ ON DUPLICATE KEY UPDATE
col_name=expr
[, col_name=expr] ... ]

Or:

INSERT [LOW_PRIORITY | HIGH_PRIORITY] [IGNORE]
[INTO] tbl_name [(col_name,...)]
SELECT ...
[ ON DUPLICATE KEY UPDATE
col_name=expr
[, col_name=expr] ... ]

示例:

INSERT INTO students (Name,Age,Gender) VALUES ('CKH',100,'M');
INSERT INTO students SET Name='ckh',Age=100,Gender='M';
INSERT INTO stu SELECT * FROM students WHERE Age > 30;

DELETE

DELETE [LOW_PRIORITY] [QUICK] [IGNORE] FROM tbl_name
[WHERE where_condition]
[ORDER BY ...]
[LIMIT row_count]

注意:一定要有限制条件,否则将清空表中的所有数据;

限制条件:WHERE、LIMIT

示例:

DELETE FROM students WHERE StuID = 18;

UPDATE

UPDATE [LOW_PRIORITY] [IGNORE] table_reference
SET col_name1={expr1|DEFAULT} [, col_name2={expr2|DEFAULT}] ...
[WHERE where_condition]
[ORDER BY ...]
[LIMIT row_count]

注意:一定要有限制条件,否则将修改所有行的指定字段;

限制条件:WHERE、LIMIT

示例:

UPDATA students SET Name='CKH',Age=100,Gender='M' WHERE StuID=10;

 

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