4.mysql数据库创建,表中创建模具模板脚本,mysql_SQL99标准连接查询(恩,外部连接,全外连接,交叉连接)
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mysql数据库创建,表创建模等模板脚本
-- 用root用户登录系统,运行脚本
-- 创建数据库 create database mydb61 character set utf8 ;
-- 选择数据库 use mydb61;
-- 添加 dbuser1 用户 -- 创建用户‘dbuser61’password为 ‘dbuser61’拥有操作数据库mydb61的全部权限 GRANT ALL ON mydb61.* TO dbuser61 IDENTIFIED BY "dbuser61"; flush privileges;
-- grant select,insert,update,delete on mydb61.* to dbuser61@localhost identified by "dbuser61"; -- grant select,insert,update,delete on mydb61.* to dbuser61@'%' identified by "dbuser61";
-- 创建表
-- 创建部门表 并赋值 DROP TABLE IF EXISTS `dept`; CREATE TABLE `dept`( `deptno` int(2) PRIMARY KEY, `dname` varchar(14) NOT NULL, `loc` varchar(13) )DEFAULT CHARSET=utf8;
INSERT INTO dept VALUES(10, 'ACCOUNTING', 'NEW YORK'); INSERT INTO dept VALUES(20, 'RESEARCH', 'DALLAS'); INSERT INTO dept VALUES(30, 'SALES', 'CHICAGO'); INSERT INTO dept VALUES(40, 'OPERATIONS', 'BOSTON');
commit;
-- 注意mysql的sql语言 约束假设起名字,须要单独写在表后面 -- 创建员工表 并赋值 DROP TABLE IF EXISTS `emp`; CREATE TABLE `emp`( -- `empno` int(4) constraint emp_empno_pk PRIMARY KEY, `empno` int(4) PRIMARY KEY, `ename` varchar(10) NOT NULL, `job` varchar(9), `mgr` int(4), `hiredate` DATE, `sal` int , `comm` int, `deptno` int(2) , constraint emp_deptno_fk foreign key(deptno) references dept(deptno) )DEFAULT CHARSET=utf8;
--创建索引 -- CREATE INDEX MYSCOTT.IX_CAtbAuditOperInfo_OT ON MYSCOTT.EMP(ENAME) TABLESPACE ts_myscott2; create index emp_ename_index on emp(ename);
--注意 日期格式不一样 INSERT INTO emp VALUES(7369, 'SMITH', 'CLERK', 7902, '1980-12-17', 800, NULL, 20); INSERT INTO emp VALUES(7499, 'ALLEN', 'SALESMAN', 7698, '1981-02-20', 1600, 300, 30); -- INSERT INTO emp(empno, ename, job, mgr, hiredate, sal, deptno) VALUES(7499, 'ALLEN', 'SALESMAN', 7698, '1981-02-20', 1600, 30); INSERT INTO emp VALUES(7521, 'WARD', 'SALESMAN', 7698, '1981-02-22', 1250, 500, 30); INSERT INTO emp VALUES(7566, 'JONES', 'MANAGER', 7839, '1981-04-02', 2975, NULL, 20); INSERT INTO emp VALUES(7654, 'MARTIN', 'SALESMAN', 7698, '1981-09-28', 1250, 1400, 30); INSERT INTO emp VALUES(7698, 'BLAKE', 'MANAGER', 7839, '1981-05-01', 2850, NULL, 30);
INSERT INTO emp VALUES(7782, 'CLARK', 'MANAGER', 7839, '1981-06-09', 2450, NULL, 10); INSERT INTO emp VALUES(7788, 'SCOTT', 'ANALYST', 7566, '1987-04-19', 3000, NULL, 20); INSERT INTO emp VALUES(7839, 'KING', 'PRESIDENT', NULL, '1981-11-17', 5000, NULL, 10);
INSERT INTO emp VALUES(7844, 'TURNER', 'SALESMAN', 7698, '1981-09-08', 1500, 0, 30); INSERT INTO emp VALUES(7876, 'ADAMS', 'CLERK', 7788, '1987-05-23', 1100, NULL, 20); INSERT INTO emp VALUES(7900, 'JAMES', 'CLERK', 7698, '1981-12-03', 950, NULL, 30);
INSERT INTO emp VALUES(7902, 'FORD', 'ANALYST', 7566, '1981-12-03', 3000, NULL, 20); INSERT INTO emp VALUES(7934, 'MILLER', 'CLERK', 7782, '1982-01-23', 1300, NULL, 10); commit;
-- 创建工资级别表 并赋值 DROP TABLE IF EXISTS `salgrade`; CREATE TABLE `salgrade`( `grade` int, `losal` int, `hisal` int )DEFAULT CHARSET=utf8;
INSERT INTO salgrade VALUES(1, 700, 1200); INSERT INTO salgrade VALUES(2, 1201, 1400); INSERT INTO salgrade VALUES(3, 1401, 2000); INSERT INTO salgrade VALUES(4, 2001, 3000); INSERT INTO salgrade VALUES(5, 3001, 9999); commit;
--创建奖金表 DROP TABLE IF EXISTS `bonus`; CREATE TABLE bonus( `ename` VARCHAR(10), `job` VARCHAR(9), `sal` int, `comm` int )DEFAULT CHARSET=utf8;
commit; |
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mysql_SQL99标准的连接查询(内连接。外连接,满外连接,交叉连接)
使用SQL99标准的连接查询(JOIN..ON..)
内连接(innerjoin等价于oracle中的“逗号”,以下的on替换掉了where)
仅仅返回满足连接条件的数据(两边都有的才显示)。
Mysql |
Oracle |
select e.*, d.* from emp e inner join dept d on e.deptno=d.deptno |
select e.*, d.* from emp e, dept d where e.deptno=d.deptno; |
-- 也能够省略innerkeyword。
左外连接
左边有值才显示。
Mysql |
Oracle |
select e.*, d.* from emp e left outer join dept d on e.deptno=d.deptno |
select e.*, d.* from emp e , dept d where e.deptno=d.deptno(+) |
-- 也能够省略outerkeyword
右外连接
右边边有值才显示。
Mysql |
Oracle |
select e.*, d.* from emp e right outer join dept d on e.deptno=d.deptno |
select e.*, d.* from emp e , dept d where e.deptno(+)=d.deptno |
-- 也能够省略outerkeyword
满外联接
任一边有值就会显示。
selecte.*, d.*
fromemp e
fullouter join dept d
one.deptno=d.deptno
--也能够省略outerkeyword
交叉连接:
叉集,就是笛卡尔积
selecte.*, d.*
fromemp e
crossjoin dept d
--没有连接条件
eg:查询员工信息,员工号,姓名,月薪,部门名称 select e.empno, e.ename, e.sal, d.dname from emp e, dept d where e.deptno=d.deptno
select e.empno, e.ename, e.sal, d.dname from emp e inner join dept d -- 逗号join on e.deptno=d.deptno -- where on
//显示全部部门信息 //显示各个部门的部门人数 select d.deptno 部门号, d.dname 部门名称,count(e.empno) 人数 from emp e, dept d where e.deptno(+)=d.deptno group by d.deptno, d.dname
select d.deptno 部门号, d.dname 部门名称,count(e.empno) 人数 from emp e right outer join dept d on e.deptno=d.deptno group by d.deptno, d.dname
自连接: -- 查询员工信息 ,老板信息 显示: ****的老板是**** select e.ename , b.ename from emp e, emp b where e.mgr=b.empno
select concat ( concat(e.ename, '的老板是'), b.ename) from emp e, emp b where e.mgr=b.empno
select e.ename, ifnull(b.ename,'他自己') from emp e left outer join emp b on e.mgr=b.empno
select concat ( concat(e.ename, '的老板是'), ifnull(b.ename,'他自己')) from emp e left outer join emp b on e.mgr=b.empno +------------------------------------------------------------------------+ | concat ( concat(e.ename, '的老板是'), ifnull(b.ename,'他自己')) | +------------------------------------------------------------------------+ | SMITH的老板是FORD | | ALLEN的老板是BLAKE | | WARD的老板是BLAKE | | JONES的老板是KING | | MARTIN的老板是BLAKE | | BLAKE的老板是KING | | CLARK的老板是KING | | SCOTT的老板是JONES | | KING的老板是他自己 | | TURNER的老板是BLAKE | | ADAMS的老板是SCOTT | | JAMES的老板是BLAKE | | FORD的老板是JONES | | MILLER的老板是CLARK | +------------------------------------------------------------------------+
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方法:按住alt键以后,鼠标拖动,选中一个矩形区域
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