Oracle Xe installation and user operation

install

install Oracle database

resources

1）OracleXE112_Win64.zip Database service management platform

2）plsqldeveloper_x64.rar Third party clients

Oracle It's a software company . this home 1977 The software company founded in California is the first in the world to launch a relational data management system （RDBMS） The company .

Now? , their RDBMS It is widely used in various operating environments ：Windows NT、 be based on UNIX The minicomputer of the system 、IBM Mainframe and some special hardware operating system platforms . in fact ,Oracle Has become the largest in the world RDBMS supplier , And is the world's leading supplier of information processing software .

Orace11g And Oracle 11g XE difference ：

Oracle Database 11g Express yes Oracle A free version of the database , Supports most of the features of the Standard Version , It takes up little memory , Very good . Is worth to recommend .

• 11g XE Provide Windows and Linux edition .
• As free Oracle Database version ,XE The restrictions are ：
  • The maximum database size is 11 GB
  • The maximum memory available is 1G
  • Only one... Can be installed on a machine XE example
  • XE Only single can be used CPU, Can't be more CPU Distribution processing on

Installation precautions

• Cannot store in Chinese Directory
• Remember the password

Oracle service

Oracle In the service

oracle It is based on service database system , It can only be used after the service is started Oracle database

1. OracleJobSchedulerXE : It is an external scheduling task service , be responsible for Oracle Scheduling tasks in . It's only in 10.1 Available after version . Generally speaking, it is useless .
2. OracleMTSRecoveryService : When Oracle Participate in Microsoft Transaction Server For distributed transactions , This matter is responsible for solving the questionable matters .
3. OracleServiceXE : yes ORCL Library Services , It is responsible for Oracle And the foundation of database startup . Only when the service is started ,Oracle The database can be started normally .
4. OracleXEClrAgent : stay Windows On the platform ,Oracle Provide CLR Integrate . because CLR The operation is to use extproc Process running , Therefore, it is usually used in a single session （ Single thread ）extproc To complete . This may not be processing CLR The best way to call .ClrAgent Provides a multithreading mechanism , So single extproc Processes can serve multiple CLR call .
5. OracleXETNSListener : This service is responsible for listening for incoming connections and passing successful connections to the database engine . Please note that , If this service is shut down , You will not be able to connect to the database remotely . Existing connections will not be affected .

start and stop service

start-up OracleServiceXE and OracleXETNSListener It can be used normally Oracle Database .

• Start and stop under the console Oracle Server command

net start OracleServiceXE

net stop OracleServiceXE

• Right click in the service panel to stop and start the service

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Oracle client

sqlplus client

Oracle After installation , A client with its own console , It's called sqlplus, With this client , At least there are available clients when you maintain the server , It's not easy to use , But better than nothing .

Use sqlplus Two steps are needed.

• First step ： Start client

Enter in the console sqlplus /nolog Start client , Note that only the client is started at this time , I haven't logged in to Oracle.

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• The second step ： Log in to Oracle

  Input at the client conn system/manager as sysdba; Log in to oracle

  • conn Is the connection oracle The order of
  • system yes oracle My administrator account
  • manager yes system The default password for the account , You can use any password when connecting to this machine , Try it
  • as Is the key word , Fixed writing
  • sysdba Is the login identity , Indicates the system database administrator , This identity has the highest authority

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• stay sqlplus Practice several common commands in

• select * from all_users; --  View all users 
  select * from dba_roles; --  View all roles 
  

  plsqldeveloper client

  plsqldeveloper It's a visual interface .

  

  • stay Command windows Window practice a few common commands , And sqlplus Compare the client

  select * from all_users; -- View all users 
  select * from dba_roles; -- View all roles 
  

  • plsqldeveloper Of SQL cache
    • plsqldeveloper Always cache the last one by default sql sentence
    • Use ed Command to open cache 【 Can edit 】
    • Use / Execute the commands in the cache
  • Tips: ：Oracle The command of is given with a semicolon （;） ending , Represents the completion and execution of an order , The system will also store the command in the cache , Only recently executed commands are stored in the cache , If you re execute the command in the cache , Use the left slash directly （/）. If the command doesn't end with a semicolon , This command just writes to the cache to save , But it doesn't carry out .

  Oracle The permissions

  System permissions refer to the execution of specific types of SQL The power of command , It is used to control one or a kind of database operations performed by users

  System permissions	effect
  CREATE SESSION	Connect to database
  CREATE TABLE	Build table
  CREATE TABLESPACE	Create a table space
  CREATE VIEW	Create view
  CREATE SEQUENCE	Set up a sequence
  CREATE USER	Build users

Oracle The role of

What is a character （role）

If multiple users need the same multiple permissions , Then it is cumbersome to assign multiple permissions to each user . To do this, you can combine multiple permissions into one role , Assign roles to multiple users , This allows each user to have the same permissions .

A role is a collection of related permissions , The main purpose of using roles is to simplify permission management .

Three standard roles

connect role( Connect characters )

• – Temporary users , It refers to users who do not need to create tables , Usually only give them connect role.
• –connect It's using oracle Simple permissions , This permission only has access to other users' tables , Include select/insert/update and delete etc. .
• – Have connect role Users can also create tables 、 View 、 Sequence (sequence)、 cluster (cluster)、 A synonym for (synonym)、 Come back (session) And others Data chain (link)

resource role( Resource role )

• - More reliable and formal database users can grant resource role.
• –resource Give users additional rights to create their own tables 、 Sequence 、 The process (procedure)、 trigger (trigger)、 Indexes (index) And clusters (cluster).

dba role( Database administrator role )

• –dba role Have all system permissions
• – Including unlimited space limits and the ability to grant various permissions to other users .system from dba The user owns

ql/sql developer The client connects three identities or roles

sysoper

Database Operator , Authority includes ： Open the database server 、 Shut down the database server 、 Backup database 、 Recover database 、 Log filing 、 Session restrictions .

sysdba

Database administrator , Authority includes ： Open the database server 、 Shut down the database server 、 Backup database 、 Recover database 、 Log filing 、 Session restrictions 、 management function 、 Create database .sys Users have to use sysdba I can only log in with my identity ,system Users can log in as normal .

normal

Ordinary users , The permission is only to query the data of some data tables . The default identity is normal user .

Oracle Users in

MySql and Oracle

• Oracle： One project corresponds to one user 【 Generally, there are many users in a database There are many tables below the user 】
• MySql： A project corresponds to a database

Although a Oracle Multiple databases can be installed in the database server , But a database needs to occupy a very large memory space , Therefore, generally a server only installs one database . Every database can have many users , Different users have their own database objects （ such as ： Database table ）, If a user accesses another user's database object , Must be granted certain permissions by the opposite user . Tables created by different users , Can only be accessed by the current user . So in Oracle In development , Different applications can be accessed by different users .

sysdba Users of roles

• user ：sys, password ：change_on_install
• user ：system, password ：manager

Recommended system user

reflection ： If the password of a company's database account is lost , What do I do ？

answer ： You can login to this machine with any password , Then change the user password 【 You can enter any password on this computer to log in to the database , But remote cannot 】

normal Users of roles scott

meanwhile Oracle It provides an ordinary user for program testing scott,XE By default, the version does not come with scott user , You can import scott The user to oracle in

Prerequisite ： Use system The user login

Import scott user

First step ： find scott.sql Script

​ stay oracle Found under the installation path scott.sql Script files , The file is located at oracle\product\11.2.0\server\rdbms\admin Under the table of contents

The second step ： Use @ Import scott Script

@C:\oraclexe\app\oracle\product\11.2.0\server\rdbms\admin\scott.sql

The third step ： Reset password and login status

alter user scott identified by tiger;
alter user scott account unlock;

user ：scott, password ：tiger

There are four tables under this user , For learning to use .

• Departmental table ：dept

desc dept; -- see dept Table structure 

№	name	type	describe
1	DEPTNO	NUMBER(2)	Indicates the department number , It consists of two digits
2	DNAME	VARCHAR2(14)	Department name , At most by 14 Composed of characters
3	LOC	VARCHAR2(13)	Location of the Department

select * from dept;

• Employee list ：emp

desc emp; -- see emp Table structure 

№	name	type	describe
1	EMPNO	NUMBER(4)	Employee's number , It consists of four digits
2	ENAME	VARCHAR2(10)	The name of the employee , from 10 Bit characters make up
3	JOB	VARCHAR2(9)	The position of an employee
4	MGR	NUMBER(4)	The leader number of the employee , Leaders are also employees
5	HIREDATE	DATE	Employee's employment date
6	SAL	NUMBER(7,2)	Basic salary , There are two decimal places , Quintuple integer , There are seven of them
7	COMM	NUMBER(7,2)	Bonus , commission
8	DEPTNO	NUMBER(2)	Employee's department number

select * from emp;

• Pay scale ：salgrade

desc salgrade; -- see salgrade Table structure 

№	name	type	describe
1	GRADE	NUMBER	The level of pay
2	LOSAL	NUMBER	The minimum wage for this level
3	HISAL	NUMBER	The highest wage in this class

select * from salgrade;

• payroll ：bonus

desc bonus; -- see bonus Table structure 

№	name	type	describe
1	ENAME	VARCHAR2(10)	Name of employee
2	JOB	VARCHAR2(9)	Employee position
3	SAL	NUMBER	Employees' wages
4	COMM	NUMBER	Employees' bonuses

select * from bonus;

Custom user

When developing the project , You need to create users for the project

Create user

• grammar ：CREATE USER user name IDENTIFIED BY password （ password ） [ACCOUNT LOCK/UNLOCK]

• CREATE USER GPB IDENTIFIED BY 123 ACCOUNT LOCK; --  Accounts cannot start with numbers 
  

Lock / Unlocking users

• grammar ：ALTER USER user name ACCOUNT LOCK/UNLOCK;

• ALTER USER GPB ACCOUNT UNLOCK;
  

Change Password

• grammar ：ALTER USER user name IDENTIFIED BY New password （ New password ）;

• ALTER USER GPB IDENTIFIED BY 123456;
  

Delete user

• grammar ：DROP USER user name

• DROP USER GPB;
  

User's role

Although the user successfully created , But I can't log in normally Oracle Database system , Because the user does not have any permissions . If the user can log in normally , Need at least CREATE SESSION System permissions . In general , An ordinary user （ Such as scott）, Have CONNECT and RESOURCE Two roles can be used for regular database development .

Grant authority

grammar ：GRANT role | jurisdiction TO user （ role ）

GRANT CONNECT TO TOM;

GRANT RESOURCE TO TOM;

give TOM user Connect Roles and Resource After the character ,jerry Users can work normally .

Recycling permissions

REVOKE role | jurisdiction FROM user （ role ）

REVOKE CONNECT FROM TOM;

REVOKE RESOURCE FROM TOM;

--  Write it together 
GRANT CONNECT, RESOURCE,DBA TO TOM;
REVOKE DBA FROM TOM;

Authorize other users to access the table

grammar ：grant jurisdiction on surface to user

eg：scott User dept Table authorized to kaifamiao user

grant all on dept to kaifamiao;

eg：kaifamiao User view scott User dept surface

select * from scott.dept;

Tips ： The user must be written . Table name , For example, in this example scott.dept;

 Please enter a user name :  SYSTEM                            
 enter your password :                                          
 Connect to :                                       
Oracle Database 11g Express Edition Release                                      
SQL> grant all on kaifamiao.infos to scott;                                 
 Authorized success .   
SQL> exit;                                 
 from  Oracle Database 11g Express Edition Relea                                          
D:\Tool\cmder>sqlplus                                                                 
SQL*Plus: Release 11.2.0.2.0 Production on                                     
Copyright (c) 1982, 2014, Oracle.  All righ                                         
 Please enter a user name :  scott                             
 enter your password :                                                                             
 Connect to :                                       
Oracle Database 11g Express Edition Release                                    
SQL> select * from infos;                  
select * from infos                        
              *                            
 The first  1  Line error :                                 
ORA-00942:  Table or view does not exist                                  
SQL> select * from scott.infos;            
select * from scott.infos                  
                    *                      
 The first  1  Line error :                                 
ORA-00942:  Table or view does not exist                                                                          
SQL> select * from kaifamiao.infos;                                    
 No line selected                                           
SQL>                                       

Summary of commands

--  Check the version of the database 
SQL> select * from v$version;

BANNER
--------------------------------------------------------------------------------
Oracle Database 11g Express Edition Release 11.2.0.2.0 - 64bit Production
PL/SQL Release 11.2.0.2.0 - Production
CORE    11.2.0.2.0      Production
TNS for 64-bit Windows: Version 11.2.0.2.0 - Production
NLSRTL Version 11.2.0.2.0 - Production

--  Single-line comments 
/**  Multiline comment  */

--  Create user 
 grammar ：CREATE USER  user name  IDENTIFIED BY  password  [ACCOUNT LOCK|UNLOCK]
eg:  CREATE USER LZY IDENTIFIED BY 123 ACCOUNT UNLOCK;

--  Assign user database roles （CONNECT role |RESOURCE role |DBA role ）
 grammar ：GRANT  role | jurisdiction  TO  user 
eg:  GRANT CONNECT, RESOURCE, DBA TO LZY;

--  Syntax for reclaiming permissions 
 grammar ：REVOKE  role | jurisdiction  FROM  user 
eg:  REVOKE DBA FROM LZY;

--  Change Password  
 grammar ：ALTER USER  user name  IDENTIFIED BY  New password 
eg:  ALTER USER LZY IDENTIFIED BY 456;

--  The modification user is locked （ Non locking ） state 
eg: ALTER USER LZY ACCOUNT LOCK;

-- dual Virtual table (dual It's a virtual table , Used to make up select Grammatical rules ,oracle Guarantee dual There will always be only one record . We can do a lot of things with it .)
SELECT SYSDATE,SYSTIMESTAMP FROM dual; --  Get system time 
SELECT SYS_CONTEXT('USERENV','TERMINAL') FROM dual;--  Get the hostname 

select * from all_tables where owner='SCOTT';-- TEST Username , The user name must be in upper case .

--  View the table of currently logged in users :
select table_name from user_tables;

Oracle data type

Some common data types

type	meaning
CHAR(length)	Stores a fixed length string . Parameters length The length is specified , If the length of the stored string is less than length, Fill in with blanks . The default length is 1, Not more than 2000 byte .
VARCHAR2(length)	Store variable length strings .length Specifies the maximum length of the string . The default length is 1, Not more than 4000 character .
NUMBER(p,s)	You can store floating point numbers , You can also store integers ,p Represents the maximum number of digits of a number （ If it is a decimal, it includes integer part, decimal part and decimal point ,p The default is 38 position ）,s Is the number of decimal places .
DATE	Store date and time , Storage era 、4 Year of the year 、 month 、 Japan 、 when 、 branch 、 second , The storage time is from... BC 4712 year 1 month 1 From the th day to the second day of A.D 4712 year 12 month 31 Japan .
TIMESTAMP	Not only the year, month and day of the storage date , Minutes and seconds , And seconds later 6 position , It also contains the time zone .
CLOB	Store large text , Such as storing unstructured XML file
BLOB	Storing binary objects , As in Figure 、 video 、 Voice etc. .

Tips: ：

• MySql Of DATE： Specific date

• DATETIME： Mm / DD / yyyy HHM / S

• MySQL character string ：varchar type

• Oracle character string ：varchar2: type

problem

• char and varchar2 The difference between
  • char： Fixed length How old are you He saves as much Fill in the extra space
  • varchar2： Variable length How much do you give How much does he use Don't use too much You can't save it without
  • Both save strings

NUMBER Type examples

Format	Input number	The actual storage
NUMBER	1234.567	1234.567
NUMBER（6,2）	123.4567	123.46
NUMBER（4,2）	12345.67	The entered number exceeds the specified precision , The database cannot store

The date type

For date types , have access to sysdate The built-in function can get the current system date and time , return DATE type , use systimestamp Function can return the current date 、 Time and time zone .

Create tables and constraints

establish infos surface （ Student list ）

CREATE TABLE INFOS
(
  STUID VARCHAR2(7) NOT NULL,       -- Student number   Student number =‘S’+ Class number +2 Bit number  
  STUNAME VARCHAR2(10) NOT NULL,  -- full name 
  GENDER VARCHAR2(4) NOT NULL,     -- Gender  
  AGE NUMBER(2) NOT NULL,           -- Age 
  SEAT NUMBER(2) NOT NULL,          -- Seat number 
  ENROLLDATE DATE,                    -- Admission time 
  STUADDRESS VARCHAR2(50) DEFAULT ' The address is unknown ',  -- address 
  CLASSNO VARCHAR2(4) NOT NULL                 -- Class number   Class number = Semester serial number + Class number  
)
/
ALTER TABLE INFOS ADD CONSTRAINT PK_INFOS PRIMARY KEY(STUID)
/
ALTER TABLE INFOS ADD CONSTRAINT CK_INFOS_GENDER  
CHECK(GENDER = ' male ' OR GENDER = ' Woman ')
/
ALTER TABLE INFOS ADD CONSTRAINT CK_INFOS_SEAT 
CHECK(SEAT >=0 AND SEAT <=50)
/
ALTER TABLE INFOS ADD CONSTRAINT CK_INFOS_AGE  
CHECK(AGE >=0 AND AGE<=100)
/
ALTER TABLE INFOS ADD CONSTRAINT CK_INFOS_CLASSNO  
CHECK((CLASSNO >='1001' AND CLASSNO<='1999') OR 
(CLASSNO >='2001' AND CLASSNO<='2999'))
/
ALTER TABLE INFOS ADD CONSTRAINT UN_STUNAME UNIQUE(STUNAME)
/

analysis ：

• Created infos surface
• STUID Column added primary key constraint
• GENDER Added check constraint , Only “ male ” and “ Woman ”
• SEAT Column added check constraint , Only in 0 To 50 Between
• AGE Column added check constraint , Only in 0 To 100 Between
• CLASSNO Column added check constraint , Only in 2001 To 2999 Between

establish scores surface （ League tables ）

CREATE TABLE SCORES
(
     ID NUMBER ,                                 --ID 
     TERM VARCHAR2(2),					     -- semester  S1 or S2
	STUID VARCHAR2(7) NOT NULL,			-- Student number 
	EXAMNO VARCHAR2(7) NOT NULL,			-- Examination number  E+ Class number + Serial number  
	WRITTENSCORE NUMBER(4,1) NOT NULL,	-- Written test results 
	LABSCORE NUMBER(4,1) NOT NULL		     -- Machine test results 
)
/
ALTER TABLE SCORES 
	ADD CONSTRAINT CK_SCORES_TERM CHECK(TERM = 'S1' OR TERM ='S2')
/
ALTER TABLE SCORES 
	ADD CONSTRAINT FK_SCORES_INFOS_STUID FOREIGN KEY(STUID) REFERENCES INFOS(STUID)  
/

analysis ：

• TERM Column added check constraint , Its value is S1 perhaps S2
• STUID Set column to foreign key column , Refer to the INFOS Tabular STUID Column

establish emp and dept surface ：

D:\Tool\cmder>sqlplus
SQL*Plus: Release 11.2.0.2.0 Production on  Monday  10 month  18 20:26:17 2021
Copyright (c) 1982, 2014, Oracle.  All rights reserved.
 Please enter a user name :  kaifamiao
 enter your password :
 Connect to :
Oracle Database 11g Express Edition Release 11.2.0.2.0 - 64bit Production
SQL> CREATE TABLE DEPT(deptid int, deptname varchar2(20), deptaddr varchar2(13), datetime date);
 Table created .
SQL> ALTER TABLE DEPT ADD CONSTRAINT pk_deptid PRIMARY KEY(deptid);
 The table has been changed .
SQL> CREATE TABLE EMP(empid int, deptid int, empname varchar2(20), job varchar2(20), manager int, entrydate date, salary float, bonus float);
 Table created .
SQL> ALTER TABLE EMP ADD CONSTRAINT pk_empid PRIMARY KEY(empid);
 The table has been changed .
SQL> ALTER TABLE EMP ADD CONSTRAINT fk_deptid FOREIGN KEY(deptid) REFERENCES DEPT(deptid);
 The table has been changed .
SQL>

CRUD operation

1、 Data manipulation language （DML）： Commands used to manipulate data in a database . Include ：select、insert、update、delete. 
2、 Data definition language （DDL）： To build a database 、 Database objects and commands for defining columns . Include ：create、alter、drop. 
3、 Data control language （DCL）： Used to control access permissions for database components 、 Authority, etc . Include ：grant、deny、revoke. 
4、 Other language elements ： Such as process control language 、 Nested Function 、 Batch statements, etc .

MySql and Oracle Some of them Sql The gap between

Date value

• MySql Insert date in ：insert into tablename (date) values('2021-10-10'), values('2000-10-01');
• Oracle：insert into tablename (date) values(to_date(‘2021-10-10 13:13:13’,’YYYY-MM-DD HH24:MI:SS’));
  • Oracle Do not interpolate contiguously Date with to_date Function handles inserts Mm / DD / yyyy HHM / S

Self growth

• MySql： Bring their own auto_increment Self increasing constraint

• Oracle： You have to customize a sequence （Sequence） To define self growth

  CREATE SEQUENCE myseq;
  SELECT myseq.nextval from dual;--  Self increasing serial number 【 Add one to the serial number 】
  select myseq.currval from dual;--  Current serial number 【 The serial number remains the same 】
  

insert data

INSERT INTO "INFOS" VALUES ('s100102', ' Lin Chong ', ' male ', '22', '2', TO_DATE('2009-08-09 06:30:10', 'YYYY-MM-DD HH24:MI:SS'), ' Xi'an ', '1001');
INSERT INTO "INFOS" VALUES ('s100104', ' Ruan Xiaoer ', ' male ', '26', '3', TO_DATE('2021-10-18 21:16:10', 'YYYY-MM-DD HH24:MI:SS'), '', '1001');

analysis ：

• insert Statement inserts data into the cache by default , Not directly inserted into the Library .
• commit Is to operate the user （ add to 、 Delete 、 Modify the operating ） Submit , Only after submitting the operation , Data can be really updated into the table , Otherwise, other users cannot query the results of the current user's operation .
• It can't be with mysql Insert as many pieces of data together , Only one by one insert

Query data

SELECT STUNAME,GENDER,AGE,STUADDRESS 
FROM INFOS 
WHERE GENDER=' male ' ORDER BY AGE

Try paging queries

SELECT * FROM 
( 
  select rownum as r ,t.* from dept t where rownum<=4
)
where r > 2

Data update

SQL> UPDATE INFOS SET CLASSNO='1002',STUADDRESS=' Laiwu, Shandong ' 
WHERE STUNAME=' Ruan Xiaoer '; 
1 rows updated 
SQL> commit;

Delete data

SQL> DELETE FROM INFOS WHERE STUID='s100102'; 
1 ROW DELETED 
SQL> COMMIT;

except Delete Statement to delete data ,truncate Statements can also delete statements

truncate table infos;

TRUNCATE The command can delete all the data in the table at one time .

TRUNCATE and DELETE All the data in the table can be deleted , The difference between them is ：

• TRUNCATE yes DDL command , Deleted data cannot be recovered ;DELETE The order is DML command , The deleted data can be recovered through log files .
• If there are many data records in a table ,TRUNCATE relative DELETE Fast .
• because TRUNCATE Orders are dangerous , So in the actual development ,TRUNCATE Use commands with caution .

Try paging queries

SELECT * FROM 
( 
  select rownum as r ,t.* from dept t where rownum<=4
)
where r > 2

Data update

SQL> UPDATE INFOS SET CLASSNO='1002',STUADDRESS=' Laiwu, Shandong ' 
WHERE STUNAME=' Ruan Xiaoer '; 
1 rows updated 
SQL> commit;

Delete data

SQL> DELETE FROM INFOS WHERE STUID='s100102'; 
1 ROW DELETED 
SQL> COMMIT;

except Delete Statement to delete data ,truncate Statements can also delete statements

truncate table infos;

TRUNCATE The command can delete all the data in the table at one time .

TRUNCATE and DELETE All the data in the table can be deleted , The difference between them is ：

• TRUNCATE yes DDL command , Deleted data cannot be recovered ;DELETE The order is DML command , The deleted data can be recovered through log files .
• If there are many data records in a table ,TRUNCATE relative DELETE Fast .
• because TRUNCATE Orders are dangerous , So in the actual development ,TRUNCATE Use commands with caution .