SQL语句PART11
1. My test: (create and grant the sysdba to a new user by SQL*Plus)
CREATE USER FJTEST1 IDENTIFIED BY JEANJEANFANG;
GRANT SYSDBA TO FJTEST;
REVOKE SYSDBA from FJTEST;
CONNECT FJTEST1/JEANJEANFANG AS SYSDBA;
2. Using ORAPWD in windows:
C:\» ORAPWD;
(show help information)
3. to see the password file:
Grammer: ORACLE_BASE\ORACLE_HOME\database» attrib
F:\oracle\ora92\database\attrib
** if want to create a user that can be connect as normal and can create table, you should grant “create session”, “resource” privileges to the user or it cannot connect as normal.
e.g.:
SQL»create user fj identified by fj;
SQL»grant create session to fj;
SQL»grant resource to fj;
Then the user “fj” can be connected as “normal” and the schema belonging to this user will be created, where he/she can create tables.
SQL» select * from user_sys_privs;
Use above statements to check user’s own system privileges.
2．How to create password file using ORAPWD
F:\oracle\ora92\database\ORAPWD FILE=F:\oracle=ora92\database\PWDmydb.ora PASSWORD=oracle ENTRIES=30
F:\oracle\ora92\database\sqlplus /nolog
SQL» connect SYS/oracle AS SYSDBA
ERROR: ORA-01031: insufficient privileges
(如果发生以上错误, 说明在ORACLE中开启了多于一个的数据库, 并且处于ＳＴＡＲＴＵＰ状态．此时要连接必须用: connect SYS/oracle＠SID AS SYSDBA, 必须在F:\oracle\ora92\network\admin＼ＴＮＳＮＡＭＥＳ．ＯＲＡ里面定义过， 如果连接的是个别数据库，就不会报告这样的错误)
ＴＮＳＮＡＭＥＳ．ＯＲＡ 定义方式：
FJDB.SIIC.COM =
(DESCRIPTION =
(ADDRESS_LIST =
(ADDRESS = (PROTOCOL = TCP)(HOST = fangjin)(PORT = 1521))
)
(CONNECT_DATA =
(SERVER = DEDICATED)
(SERVICE_NAME = fjdb)
)
)
** or use the following command in dos state:
C: \ set oracle_sid = “jeandb”
C:\ sqlplus /nolog
SQL» connect sys/jeandb as sysdba;
3. Ｈow to create an oracle database in windows manually
Step1: setting environment var
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有表students(name,class,grade),请用标准sql语句完成
name class grade
张三 数学 81
李四 语文 70
王五 数学 90
张三 语文 60
李四 数学 100
王五 语文 90
王五 英语 81
要求: 用sql语句输出各门功课都大于80分的同学姓名?
create table students (
name varchar(25),
class varchar(25),
grad ......
1、触发器的概念
触发器也是一种带名的PL/SQL块。触发器类似于过程和函数，因为它们都是拥有声明、执行和异常处理过程的带名PL/SQL块。与包类似，触发器必须存储在数据库中并且不能被块进行本地化声明。
对于触发器而言，当触发事件发生的时候就会显式地执行该触发器，并且触发器不接受参数。
创建触发器的语法� ......
oracle 方法 & ......
Subquery: (single-row subqueries and multi-rows subqueries).
select select_list
from table
where expr operator (select select_list from table);
single-row subqueries operator: =, >, >=, <, <=, <>
e.g.:
1. select department_id, min(salary) from employees group by department_id ......
CREATE VIEW MYVIEW
AS
SELECT * from bjxxdiweb_database2007.dbo.bm_tongji
UNION ALL
SELECT * from aa.DBO.chen
select * into aa..chen from bjxxdiweb_database2007.dbo.bm_tongji where 1=2
说明：数据库A的表的字段名必须和数据库B的表的字段名相同，包括数据类型等。 ......
