Distribution center of Program data: Database

Basic concepts of the database
1. The role of the database
① stores large amounts of data for easy retrieval and access
② keep the data information consistent and complete
③ Sharing and security
④ to generate new and useful information by combining analysis

2. Databases and Applications
① applications
Action: Responds to actions and displays results, requests data to the database
Requirements: beautiful, simple and convenient operation
② Database:
Function: Store data, examine data, generate new data
Requirements: Unity, security, performance, etc.

3. Popular databases in the enterprise
①oracle (also known as: Large database)
Oracle Company's Products
Product free, service charge
* Commonly used for large corporate fund tables
②sql Server
Microsoft Company Products
Multiple versions for different user groups
Enterprise Edition
Standard Edition
Workgroup Edition
Development version
Evaluation version
Good ease of Use
③db2
IBM Company's Products
Supports multiple operating systems, multiple types of hardware and devices
The operating system can implement cross-platform
④mysql (also called: Small database)
Developed by the Swedish MySQL AB company and is currently part of Oracle's product portfolio.
Open Source Code
Extensive website application

4. Entities in the database
Something that can be described objectively.
The "entity" is the use of tables in the database instead
"Table":
Line: Record
Columns: Fields
The database is the "warehouse" of "data"
The database contains tables, relationships, and manipulating objects
Data is stored in the table

5. Database Management (Operations)
① Retrieving data
② Inserting data
③ Updating data
④ Deleting data
Referred to as "additions and deletions to search"
Database System (DBS): Warehouses
Database management System (DBMS): Multiple users can simultaneously implement (add and revise)

6. Configuration of basic requirements for database installation:
① Processor:
Minimum 600-mhz Pentium processor.
Recommended: 1GHZ or higher
② Memory:
Min.: 512MB
Recommended: 1GB or larger
③ Disk Capacity:
360MB (Typical installation)
750MB (fully installed)
④ Operating System
Different versions of the installation support different operating systems

7. database files and transaction log files
(1) Data file
①.mdf (main data file): mainly responsible for the management and monitoring of data files (core operations), and only one
②.NDF (secondary data file): Optional, can have more than one. Assist when the primary data file data workload is too large
(2) Log file:
①.LDF: Records the running status of the entire data file, including the wrong information and records. Helps us view the performance of the database
* Log files: Generally use one, you can also use multiple

SQL Server Database
1.SQL Server service startup mode
(1) Startup of operating system services
① Click My computer → right click → manage → services and applications → services → Locate the appropriate version of SQL Server in the service → start Service → show in status column is running
②windows key +r→ input services.msc→ service → find SQL Server corresponding version in service → start Service → show in status column running is OK
(2) Startup in SQL Server Management Studio

2. Linking to the server
Server name: typically "." or "." + Server Name
Authentication: There are two types of →①sql Server authentication (user name and password required) ②windows authentication (no user name and password required)

3. system databases and user databases
(1) System database
①master (Database Core): Responsible for the entire running process of the database and monitoring the running state of the database
②model (model database): Provide user reference structure
③TEMPDB (Temporary database): Temporary data generated when we perform "additions and deletions" is saved to the staging database
④MSDB (Warning database): Store some error messages
⑤resource (Database Resource):
(2) User database
is to create the database that you use

4. Create a login name
* Create a new login and disable or delete the "SA" account to secure the database
* "SA" is the administrator's default login name
(1) Disable:
Security → login name → find login → right click → properties → status → login settings modified to Disabled
(2) Delete:
Security → login name → find login → delete
(3) New login name:
* If you disable all logins by using the administrator to qualify the bug
① using Windows identity login → security → check login name → right → new login
Fill in the login name → select the authentication type → enter password → cancel enforce password policy
Login name: In general, use the English name
Enforce password Policy: Change password every time you log in
② Modify Administrator permissions (modify to highest):
server role → Select sysadmin
③ View Status
Modify the startup status if the login has changed

5. Creation and management of databases
(1) Create:
Database → selected, right-click → Enter database name
Create secondary data file: Add → suffix name. datal
Owner: Association
Low access permissions increase when a login with a low access rights associates a logon name with a high access privilege

Distribution center of Program data: Database