数据库操作
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| SHOW DATABASES;
CREATE DATABASE xxxcompany DEFAULT CHARACTER SET utf8;
DROP DATABASE xxxcompany;
SHOW CREATE DATABASE xxxcompany;
ALTER DATABASE xxxcompany DEFAULT CHARACTER SET gbk;
USE xxxcompany;
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表格操作
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| SHOW TABLES;
CREATE TABLE department(id INT,NAME CHAR(20));
DESC department;
DROP TABLE department;
ALTER TABLE department ADD COLUMN departName VARCHAR(3);
ALTER TABLE department DROP COLUMN departName;
ALTER TABLE department MODIFY COLUMN departName VARCHAR(30);
ALTER TABLE department CHANGE COLUMN departName dept VARCHAR(30);
ALTER TABLE department RENAME TO dept;
INSERT INTO department VALUES(001,'工程部');
delete from student; delete from student where sid = 1001;
update student set username = 'lisisi' where sid = 1002;
update student set username = 'lisisisi'
SELECT * FROM 部门表;
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简单查询例子
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| SELECT * FROM student;
SELECT stuName,english FROM student;
SELECT DISTINCT english FROM student;
SELECT id AS '学号',stuName AS '姓名',chinese AS '语文',english AS '英语',math AS '数学' FROM student AS s;
SELECT * FROM student WHERE stuName LIKE '杨%';
SELECT * FROM student WHERE english > 90;
SELECT * FROM student WHERE (english + chinese + math) > 200;
SELECT english FROM student WHERE stuName LIKE '段%';
SELECT * FROM student WHERE english > 80 OR (english + chinese + math) > 200;
SELECT stuName AS '姓名',(english + chinese + math) AS '总分' FROM student;
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