SQLSERVER2 database implementation

1. database creation syntax createdatabase database name on [primary] (data file parameter [, n] [file group parameter]) [LOGON] (log file parameter [, n]) note: [] indicates the optional part, and {} indicates that you need to create some database instances: createdatabaseNetBarDBonprimary -- default

1. create database Syntax: create database name on [primary] (data file parameter [, n] [file group parameter]) [log on] (LOG file parameter [, n]) Note: "[]" indicates the optional part, and "{}" indicates that some database instances need to be created: create database NetBarDB on primary -- default

1. database creation syntax

Create database Name

On [primary]

(

<数据文件参数> [,... N] [ <文件组参数> ]

)

[Log on]

(

<日志文件参数> [,... N]

)

Note:

"[]" Indicates the optional part, and "{}" indicates the required part.

Create a database instance:

Create database NetBarDB

On primary -- by default, it belongs to the primary main file group, server space, U.S. server, which can be omitted

(

Name = 'netbar _ data', -- Logical name of the master data file

Filename = 'e: \ NetBar_mdf.mdf ', -- physical name of the master data file

Size = 3 mb, -- initial size of the master data file

Maxsize = 100 mb, -- maximum growth of the master data file

Filegrowth = 15% -- growth rate of the master data file

)

Syntax for creating database data files and log files:

Create database Name

On

{

NAME = logical NAME,

FILENAME = Name of the physical file,

SIZE = file SIZE,

MAXSIZE = maximum file length,

FILEGROWTH = automatic Growth

}

Log on

{

...........................

}

2. delete database Syntax:

Drop database name;

Delete multiple databases:

Drop database name 1, database name 2,... database name n;

Note:

Deleting a database using the drop statement will delete the database.

Disk related to the database to be deleted

Files, virtual hosts, such as data files and log files

Example of deleting a database:

If exists (select * from sysdatabases where)

Drop database NetBarDB

Go

Or:

If DB_ID ('netbardb') is not null

Drop database NetBarDB

Go

3. Table creation Syntax:

Create table Name

(

Field 1 Data Type field features,

Field 2 Data Type field features,

......

Field n data type field features,

)

4. Modify the table Syntax:

Add column:

Alter table name

Add {Field Data Type field feature} [,... n]

Delete column:

Alter table name

Drop column {field} [,... n]

Modify columns:

Alter table name

Alter column field data type [null | not null]

5. Table deletion Syntax:

Drop table Name

6. SQL Server constraints:

Purpose: To ensure the complete type of data in the table.