The first part of SQL database

Database: A program used to access data

ACCESS: Self-brought, smaller, not very professional

SQL Server: Mainly used in. NET language, more professional. Microsoft Development

MYSQL: Mainly used in the PHP language, smaller than SQL Server volume

Oracle: Used primarily in Java

Each database has a corresponding language.

Mainly because the connection is convenient, others can also be connected, but may be more troublesome than the usual.

Database has two parts: interface + Service

A service is a program that can operate in the background.

An interface is a program that can see data from a database.

The service and interface can be separated.

Only services can be used alone.

Service Open

Control Panel--management tools--Service--sql Server (MSSQLSERVER)

The database is also used in tabular format when storing data

column (field);

Line (record);

The database is like Excel, and multiple tables can appear

Windows authentication can only be used with native references

SQL Server can interoperate
Sa=super Admin

Create a database

Database size growth
Increase by MB Average
by percentage

Test

Test Master file. mdf
Test_log log files
Test1 secondary data files. ndf

The primary and log files are required, and there is only one
Number of secondary files not required

Attaching and detaching a database
Detach: Locate the database, right-click-Task-Detach, OK
After detaching, you can copy the files of the database to other computers D:\Program Files\Microsoft SQL Server
\mssql10. Mssqlserver\mssql\data

Attach: Select database, right--Attach--Popup dialog--select attached file--click Add to find the file to attach--ok

Backup and restore of databases

varchar (50) string, length in parentheses
Boolean type C#bool SQL bit

Each table must have a primary key to distinguish the same data from the primary key.

Input and data

After creating a table, you can type and change the data in the interface

The first part of SQL database