One , What can a database do ?

* Store large amount of data , Easy to query and operate
* Keep data and information consistent , complete
* Sharing and security
* Through combination analysis , Generate new and useful information
Two , Databases and Applications

* application program
* effect : Respond to actions and display results , Request data from database
* requirement : beautiful , Easy to operate
* database
* effect : Store data , Retrieve data , Generate new data
* requirement : unified , security , Performance, etc
That's ok ( record ), column ( field )

Three , Basic concepts of database

* Database is “ data ” Of “ Warehouse ”
* Table in database , Relationship and operation object
* Data stored in table
Four , Create and manage user databases

*
data file

* Main data file
* Secondary data files
*
log file

separate —> Disconnect —> move
additional —> piece in

Five , The difference between data file and log file

* data file : Include data and objects , As shown in the table , Indexes , Stored procedures and views
* log file : Contains information needed to recover all transactions in the database
Six ,Sql Server database structure

Storage structure is divided into logical storage structure ( User perspective ) And physical storage structure ( Database administrator's point of view ) two types .

* Logical storage structure : What kind of information does an index database consist of
* Physical storage structure : Discuss how database files are stored on disk
Seven ,Sql Server System database

*
Master database : record Sql Server Initialization information , database information , Login account , System level information such as system configuration settings .

*
Tempdb database : Temporary tables and stored procedures created when saving operation data .

*
Model database : Save database template . When creating a blank database , You can directly use the specified template to create .

*
Msdb database : For SQL Server The agent provides the necessary information to run the scheduling alert , Operation and record operation . It also records the backup and restore information of the database .

*
Resource database : preservation Sql Server All system objects in , Is a read-only database .

Technology
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