Program Data Center: A detailed summary of the database

database is one of the techniques that programmers must master, in the C # language, the data is stored in memory using variables, and once the program has finished running, the data in memory will disappear. If you want to keep your data for a long time, and you can organize your data. What should we do? then the database needs to be used. One : First, We understand the role of the database the role of the database:

can store large amounts of data to retrieve data and generate new data

Data consistency and integrity can be guaranteed

To meet the sharing and security requirements of your app

Convenient and intelligent analysis to generate new and useful information

Database in order to ensure the persistence of data

Perfect management of various database objects, with strong data organization, user management, security checks and other functions.

It is easy to generate a variety of data objects, using stored data to build forms and reports, good visibility.

Provides screen-oriented data entry queries and design-oriented query Language report generators

supports a wide range of hardware and operating system platforms, from desktops to large and super computers, providing a high degree of scalability for a variety of hardware architectures, supporting symmetric multiprocessor, clustered multiprocessor, large scale processors, and providing a wide range of international language support.

The system has a complete definition of triggers, stored procedures, rules and integrity, and it supports optimized queries and has better data security.

Two: a common database

Oracle

DB2

SQL Server

Mysql

Sqllite

Visual FoxPro

Access

System database:

Resource database: Role: Users create a new database school, then some information is automatically mapped from resource to school

Master database: Saves all database information and, once corrupted, the entire database software will not run.

Model: Template Database

Tempdb: Staging database, saving temporary data

MSDB: Agents, business scheduling, alert jobs, etc.

Three: The important conceptWhat does data integrity refer to? Analysis: The accuracy of data is the integrity of dataWhat are the two forms of authentication for SQL Server? Resolution: Windows Authentication and SQL Server Authentication
which two files do I need to specify to create a database? parsing: Data files (. mdf) and log files (. ldf)What is a server? Parse: A container that provides services. A service is installed on a computer, such as a database, and this computer is called a database server.Four: Important questionsWhat is the difference between DBMS and DBS? Resolution: DBS contains DBMS because of database system components: Database operator database software (database management system) the computer that hosts the softwareHow does the database service start?

Method one: To "My Computer" → Right-click "Services" →sql Server (MSSQLServer)

Method Two: Open the Start menu → run →services.msc Enter to open the service window, follow the same procedure

Method Three: Press and hold the "Win+r" on the keyboard to open the Command Prompt window, enter the →services.msc carriage return to open the service window, follow the same procedure

Method Four: Net start mssqlserver (startup) net stop MSSQLServer (paused)

How do I copy a hard disk's database file to a USB flash drive?

Parsing: By shutting down the service

How do I restore a database file from a USB flash drive to a database in the database software on my computer?

Resolution: The data file on the USB stick is copied to the computer's non-system disk, using additional tools to find the corresponding location of the database files, for additional operations

A flaw in stopping the service from backing up data files?

Parse: Hot backup!

Shrink database What do you do?

Resolution: Save Hard disk space

It's over here, take a good look.

Program Data Center: A detailed summary of the database