Oracle Learning Notes (i)

1.Oracle is the Oracle company, it should be considered a high level of the database;

2. Occupation: DBA (Database administrator)

3. Database classification://How to select a database: {1. Project size; 2. Cost; 3. Security}

A: Small database: Access, foxbase;[100 people, cost thousand yuan, security is not high]

B: Medium database: Mysql, SQL Server, INFORMLX; [Medium, 5000~1w cost, security medium]

C: Large database: Sybase < Oracle (11G, 12C) < DB2; [massive, tens of thousands of costs, highest security level]

4. Database name is less than 8 characters and cannot be Chinese;

5. Database Users:

A.sys User: Sysdba role-Password:

B.system User: Syeoper Role-Password: Manager

6.SQL statement:

Insert

Delete

Update

Select

All

CREATE index

{Conn/disc, PASSW, exit}

{Four sheets: Bonus, Dept, EMP, Salgrade}

Oracle Learning Notes (i)