今天是學數據庫的第一天，之前安裝Oracle幾經波折終於裝成功(缺監聽，加監聽和替換tns)。學習如何建表，可視畫界面直觀簡單，但還是學習用腳本語言寫出來，建了員工表，崗位表，工資等級表，剛開始建錯不懂怎么修改，是刪掉整個文件，發現內容還在，后來學到直接用語句改錯，和刪除，插入。
不管編寫幾張表，腳本都可寫在一個xx.sql
alter session set nls_date_format='yyyy-mm-dd hh:mi:ss';
insert into emp values(1001,'子容','CTO',0,'2020-11-10',2000,5000,1);
update emp set sal=20000 where empno=1001;
insert into emp values(1002,'小梅','測試',0,'2020-12-10',10000,5000,2);
insert into emp values(1003,'潔杏','前端',1005,'2020-10-10',10000,6000,3);
insert into emp values(1004,'杏群','后端',1005,'2020-10-10',11000,5000,4);
insert into emp values(1005,'港哥','后端',0,'2020-11-10',12000,6000,4);
insert into emp values(1006,'艷梅','后端',1005,'2020-10-10',11000,6000,4);
insert into emp values(1006,'家梅','美工',1005,'2020-9-10',11000,6000,5);
insert into emp values(1007,'麗蘭','HR',1001,'2020-12-10',11000,6000,6);
insert into emp values(1008,'俊宇','工程師',0,'2020-12-10',12000,6000,7);
insert into emp values(1009,'小芳','程序員',1005,'2020-11-10',12000,6000,8);
insert into emp values(1010,'黃蓉','程序員',1001,'2020-8-10',11000,6000,8);
select * from emp;
drop table DEPT;
create table dept(
deptno number(4) primary key,
dname varchar2(20),
log varchar2(20)
)
insert into dept values(1,'CTO','東');
insert into dept values(2,'測試','西');
insert into dept values(3,'前端','南');
insert into dept values(4,'后端','北');
select * from dept;
create table sallv(
lv number(4) primary key,
min number(10),
max number(10)
)
insert into sallv values(1,2000,10000);
insert into sallv values(2,10000,11000);
insert into sallv values(3,11000,12000);
update sallv set min=12000 where lv=1;
update sallv set max=20000 where lv=1;
update sallv set min=11000 where lv=2;
update sallv set max=12000 where lv=2;
update sallv set min=10000 where lv=3;
update sallv set max=11000 where lv=3;
select * from sallv;
select dname,log from dept;
select ename,sal from emp;
select 12*3 from dual;
select ename as "姓名",sal*12+comm as "年 薪" from emp;
select '姓名:'||ename as "別致的列名" from emp;
select ename as "姓名",'年薪'||(sal*12+comm) as "年 薪" from emp;
select nvl(11,1000) from dual;
select * from emp;