如果您才接触SQL不久,SQL的各种命令是一定需要掌握的,下面为您介绍SQL命令中的Drop删除表,供您参考,希望对您有所帮助。
Drop Index
取消索引
You can delete an existing index in a table with the DROP INDEX statement.
你可以将现有的索引通过DROP INDEX语句进行取消操作。
Syntax for Microsoft SQLJet (and Microsoft Access):
在Microsoft SQLJet (和 Microsoft Access)中的语法是这样的:
DROP INDEX index_name ON table_name
Syntax for MS SQL Server:
MS SQL Server的语法是这样:
DROP INDEX table_name.index_name
Syntax for IBM DB2 and Oracle:
IBM DB2和Oracle的语法为:
DROP INDEX index_name
Syntax for MySQL:
MySql则是这样:
ALTER TABLE table_name DROP INDEX index_name
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Delete a Table or Database
删除一张表或是一数据库
To delete a table (the table structure, attributes, and indexes will also be deleted):
删除一张表(表中的数据结构,属性以及索引也会被删除):
DROP TABLE table_name
To delete a database:
要删除一个数据库的话可以这样写:
DROP DATABASE database_name
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Truncate a Table
截表
What if we only want to get rid of the data inside a table, and not the table itself? Use the TRUNCATE TABLE command (deletes only the data inside the table):
当我们只想将表内的数据做完成清楚而保留其内部结构的话,可以使用TRUNCATE TABLE命令(仅仅删除表中的数据)
TRUNCATE TABLE table_name