java的征程终于到了JDBC,学习JDBC之前要复习下数据库,在网上下载的是尚学堂oracle的教材,而我本机只能装上mysql,于是就想在my
java的征程终于到了JDBC,,学习JDBC之前要复习下数据库,在网上下载的是尚学堂Oracle的教材,而我本机只能装上mysql,于是就想在mysql中创建oracle的学习用表。费了白天劲还是成功了。
创建表的时候将NUMBER换成int,varchar2换成varchar,datetime换成date,插入表的时候用DATE函数。
1.创建数据库
create database mydata;
2.使用数据库
USE mydata
3.创建dept,emp表
//创建dept表
CREATE TABLE dept
(
deptno INT PRIMARY KEY,
dname VARCHAR(14),
loc VARCHAR(13)
);
//创建emp表
CREATE TABLE EMP
(EMPNO INT(4) PRIMARY KEY,
ENAME VARCHAR(10),
JOB VARCHAR(9),
MGR INT(4),
HIREDATE DATE,
SAL DOUBLE,
COMM DOUBLE,
deptno INT,
FOREIGN KEY (deptno) REFERENCES dept(deptno)
);
//创建salgrade表
CREATE TABLE salgrade(
grade INT PRIMARY KEY,
losal INT,
hisal INT
)
4.insert数据
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');
INSERT INTO EMP VALUES
(7369,'SMITH','CLERK',7902,DATE('1980-12-17'),800,NULL,20);
INSERT INTO EMP VALUES
(7499,'ALLEN','SALESMAN',7698,DATE('1981-2-20'),1600,300,30);
INSERT INTO EMP VALUES
(7521,'WARD','SALESMAN',7698,DATE('1981-2-22'),1250,500,30);
INSERT INTO EMP VALUES
(7566,'JONES','MANAGER',7839,DATE('1981-4-2'),2975,NULL,20);
INSERT INTO EMP VALUES
(7654,'MARTIN','SALESMAN',7698,DATE('1981-9-28'),1250,1400,30);
INSERT INTO EMP VALUES
(7698,'BLAKE','MANAGER',7839,DATE('1981-5-1'),2850,NULL,30);
INSERT INTO EMP VALUES
(7782,'CLARK','MANAGER',7839,DATE('1981-6-9'),2450,NULL,10);
INSERT INTO EMP VALUES
(7788,'SCOTT','ANALYST',7566,DATE('1987-4-19'),3000,NULL,20);
INSERT INTO EMP VALUES
(7839,'KING','PRESIDENT',NULL,DATE('1981-11-17'),5000,NULL,10);
INSERT INTO EMP VALUES
(7844,'TURNER','SALESMAN',7698,DATE('1981-9-8'),1500,0,30);
INSERT INTO EMP VALUES
(7876,'ADAMS','CLERK',7788,DATE('1987-5-23'),1100,NULL,20);
INSERT INTO EMP VALUES
(7900,'JAMES','CLERK',7698,DATE('1981-12-3'),950,NULL,30);
INSERT INTO EMP VALUES
(7902,'FORD','ANALYST',7566,DATE('1981-12-3'),3000,NULL,20);
INSERT INTO EMP VALUES
(7934,'MILLER','CLERK',7782,DATE('1982-1-23'),1300,NULL,10);
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)

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