sql语言中对数据库的表的判断

 

     Obtain the database list in sql server:

USE master

SELECT * FROM sysdatabases

Database name field: name

        Check whether an database object exists:

SELECT object_id(‘object name’)

SELECT object_id(n'name','U'/'V'/'tr')

Para U:Table  V:View Tr:trigger.

// check if there is a database xjaa.

USE master

IF DB_ID(N'name') IS NULL
BEGIN
 CREATE DATABASE name

END

Return the identification of the object or null if it doesn’t exist.

        Delete database object:

DROP TABLE <tablename>

DROP TRIGGER: <triggername>

DROP DATABASE: <databasename>

          Modify database object:

ALTER DATABASE:

ALTER TABLE:

ALTER PROCEDURE

ALTER TRIGGER