From c0b58757b1ab1286367f0421b28fc21ae008fb87 Mon Sep 17 00:00:00 2001 From: xiangwbs Date: Sat, 23 Jun 2018 20:52:31 +0800 Subject: [PATCH] merge --- .../main/java/com/xwbing/demo/sql/sql01.sql | 125 +++--------------- .../main/java/com/xwbing/demo/sql/sql02.sql | 17 +-- 2 files changed, 19 insertions(+), 123 deletions(-) diff --git a/boot-service/src/main/java/com/xwbing/demo/sql/sql01.sql b/boot-service/src/main/java/com/xwbing/demo/sql/sql01.sql index 32f7d24..71d2897 100644 --- a/boot-service/src/main/java/com/xwbing/demo/sql/sql01.sql +++ b/boot-service/src/main/java/com/xwbing/demo/sql/sql01.sql @@ -1,15 +1,5 @@ -CREATE TABLE employee_xwbin( - id NUMBER(4) DEFAULT 1 , - name VARCHAR2(20), - gender CHAR(1) DEFAULT 'M', - biith DATE, - salary NUMBER(6,2), - job VARCHAR2(30), - deptno NUMBER(2) -); -DROP TABLE name4; -NOT NULL 约束可以确保指定的字段不允许为null -CREATE TABLE employ_xwbing( +DDL +CREATE TABLE xwbing( id NUMBER(4) DEFAULT 1, name VARCHAR2(20) NOT NULL, gender CHAR(1) DEFAULT 'M', @@ -19,120 +9,41 @@ CREATE TABLE employ_xwbing( deptno NUMBER(2) DEFAULT 1 ) DESC xwbing; +DROP TABLE xwbing; RENAME employ_xwbing TO xwbing; -DESC xwbing; -修改表的 向表中添加新的字段,只能在当前表的末尾追加,可以同时追加多个列,只需要使用逗号隔开即可,与创建声明列的时候语法一样 ALTER TABLE XWBING ADD( HIREDATE DATE DEFAULT SYSDATE ) -删除表中现有字段 DML -用于修改表中数据,分为:增 删 改 插入数据 -INSERT INTO XWBING (id,name,job,salary) -VALUES(1,'JACK','CLERK',5000) -COMMIT +INSERT INTO XWBING (id,name,job,salary) VALUES(1,'JACK','CLERK',5000) 插入日期类型,建议使用TO-DATE函数 -可以使用字符串 但是格式必须是'DD-MON-RR' -由于有语言差异,不推荐 -INSERT INTO XWBING(id,name,job,birth) -VALUES(2,'ROSE','CLERK',TO_DATE('1992-08-02','YYYY-MM-DD')) -SELECT *FROM XWBING; - -ALTER TABLE XWBING DROP(HIREDATE) - +INSERT INTO XWBING(id,name,job,birth) VALUES(2,'ROSE','CLERK',TO_DATE('1992-08-02','YYYY-MM-DD')) 修改表中现有字段 可以修改字段的类型,长度,默认值,非空 ALTER TABLE XWBING MODIFY( job VARCHAR2(40) DEFAULT 'CLERK' ) - 修改表中现有数据 -将rose的工资改为5500 UPDATE XWBING SET SALARY=50000 WHERE name='ROSE' 字符串里区分大小写,用'' - -修改表中的数据的时候,通常要使用WHERE下限定条件,这样只会将满足条件的记录进行修改, -若不在指定WHERE则是全表所有的数据都修改 - 删除表中数据 -将rose删除 DELETE FROM EMP_XWBING WHERE name='ROSE' -DELETE FROM EMP_XWBING -删除表中数据同样要用WHERE添加过滤条件 否则就是清空表操作 - -CREATE TABLE emp_xwbing( - empno NUMBER(4,0), - ename VARCHAR2(10), - job VARCHAR2(9), - mgr NUMBER(4,0), - hiredate DATE, - sal NUMBER(7,2), - comm NUMBER(7,2), - deptno NUMBER(2,0) -) -SELECT *FROM EMP_XWBING; -DESC emp_xwbing; -CREATE TABLE dept_xwbing( - deptno NUMBER(2,0), - dname VARCHAR2(14 BYTE), - loc VARCHAR2(13 BYTE) -) - -INSERT INTO emp_xwbing(empno, ename,job,mgr,hiredate,sal,deptno) -VALUES(7369,'SMITH','CLERK',7902,TO_DATE('1980/12/17','YYYY-MM-DD'),800.00,20); -INSERT INTO emp_xwbing(empno, ename,job,mgr,hiredate,sal,comm,deptno) -VALUES(7499,'ALLEN','SALESMAN',7698,TO_DATE('1981/02/20','YYYY-MM-DD'),1600.00,300.00,30); -INSERT INTO emp_xwbing(empno, ename,job,mgr,hiredate,sal,comm,deptno) -VALUES(7521,'WARD','SALESMAN',7698,TO_DATE('1981/02/22','YYYY-MM-DD'),1250.00,500.00,30); -INSERT INTO emp_xwbing(empno, ename,job,mgr,hiredate,sal,deptno) -VALUES(7566,'JONES','MANAGER',7839,TO_DATE('1980/4/2','YYYY-MM-DD'),2975.00,20); -INSERT INTO emp_xwbing(empno, ename,job,mgr,hiredate,sal,comm,deptno) -VALUES(7654,'MARTIN','SALESMAN',7698,TO_DATE('1981/9/28','YYYY-MM-DD'),1250.00,1400.00,30); -INSERT INTO emp_xwbing(empno, ename,job,mgr,hiredate,sal,deptno) -VALUES(7698,'BLACK','MANAGER',7839,TO_DATE('1980/5/1','YYYY-MM-DD'),2850.00,30); -INSERT INTO emp_xwbing(empno, ename,job,mgr,hiredate,sal,deptno) -VALUES(7782,'CLARK','MANAGER',7839,TO_DATE('1980/6/9','YYYY-MM-DD'),2450.00,10); -INSERT INTO emp_xwbing(empno, ename,job,mgr,hiredate,sal,deptno) -VALUES(7788,'SCOTT','ANALYST',7566,TO_DATE('1987/4/19','YYYY-MM-DD'),3000.00,20); -INSERT INTO emp_xwbing(empno, ename,job,hiredate,sal,deptno) -VALUES(7839,'KING','PRESIDENT',TO_DATE('1981/11/17','YYYY-MM-DD'),5000.00,10); -INSERT INTO emp_xwbing(empno, ename,job,mgr,hiredate,sal,comm,deptno) -VALUES(7844,'TURNER','SALESMAN',7698,TO_DATE('1981/9/8','YYYY-MM-DD'),1500.00,0.00,30); -INSERT INTO emp_xwbing(empno, ename,job,mgr,hiredate,sal,deptno) -VALUES(7876,'ADAMS','CLERK',7788,TO_DATE('1987/5/23','YYYY-MM-DD'),1100.00,20); -INSERT INTO emp_xwbing(empno, ename,job,mgr,hiredate,sal,deptno) -VALUES(7900,'JAMES','CLERK',7698,TO_DATE('1981/12/3','YYYY-MM-DD'),9500.00,30); -INSERT INTO emp_xwbing(empno, ename,job,mgr,hiredate,sal,deptno) -VALUES(7902,'FORD','ANALYST',7566,TO_DATE('1981/12/3','YYYY-MM-DD'),3000.00,20); -INSERT INTO emp_xwbing(empno, ename,job,mgr,hiredate,sal,deptno) -VALUES(7934,'MILLER','CLERK',7782,TO_DATE('1982/1/23','YYYY-MM-DD'),1300.00,10); - -INSERT INTO dept_xwbing(deptno,dname,loc) -VALUES(10,'ACCOUNTING','NEW YORK'); -INSERT INTO dept_xwbing(deptno,dname,loc) -VALUES(20,'RESEARCH','DALLAS'); -INSERT INTO dept_xwbing(deptno,dname,loc) -VALUES(30,'SALES','CHICAGO'); -INSERT INTO dept_xwbing(deptno,dname,loc) -VALUES(40,'OPERATIONS','BOSTON'); -select *from dept_xwbing; -create table name2 ( - deptno NUMBER(2,0), - dname VARCHAR2(14 BYTE), - loc VARCHAR2(13 BYTE) -); -INSERT INTO name2(deptno,dname,loc) -VALUES(10,'ACCOUNTING','NEW YORK'); -INSERT INTO name2(deptno,dname,loc) -VALUES(20,'RESEARCH','DALLAS'); -INSERT INTO name2(deptno,dname,loc) -VALUES(30,'SALES','CHICAGO'); +DQL +SELECT语句 +SELECT是用来查询数据的语句DQL +查询某张表中的所有字段的记录: +SELECT * FROM EMP_XWBING; +查看指定字段的值: +SELECT ename,sal,job FROM EMP_XWBING; -SELECT *FROM name4; -alter table name2 modify(deptno NUMBER(4,0), - dname VARCHAR2(14 BYTE)) \ No newline at end of file +DQL必须包含的部分是SELECT子句与FROM子句 +SELCET用来确定查询的字段,可以使用的有:表的字段,函数,表达式FROM子句来确定查询的表 + +SELECT中使用表达式 +查看每个员工的年薪 +SELECT ename,sal*12 FROM emp_xwbing; diff --git a/boot-service/src/main/java/com/xwbing/demo/sql/sql02.sql b/boot-service/src/main/java/com/xwbing/demo/sql/sql02.sql index f59bd84..a772bdd 100644 --- a/boot-service/src/main/java/com/xwbing/demo/sql/sql02.sql +++ b/boot-service/src/main/java/com/xwbing/demo/sql/sql02.sql @@ -1,22 +1,7 @@ -SELECT语句 -SELECT是用来查询数据的语句DQL -查询某张表中的所有字段的记录: -SELECT * FROM EMP_XWBING; -查看指定字段的值: -SELECT ename,sal,job FROM EMP_XWBING; - -DQL必须包含的部分是SELECT子句与FROM子句 -SELCET用来确定查询的字段,可以使用的有:表的字段,函数,表达式FROM子句来确定查询的表 - -SELECT中使用表达式 -查看每个员工的年薪 -SELECT ename,sal*12 FROM emp_xwbing; - - 字符串函数 1:concat(p1,p2) 连接字符串 SELECT concat(ename,sal) FROM emp_xwbing; -2:连接字符串简便方式:||,相当与java里的-+号,拼接作用 +2:连接字符串简便方式:||,相当与java里的+号,拼接作用 SELECT ename||':'||sal FROM emp_xwbing; LENGTH(p)函数,获取字符串长度