[sql] DROP IF EXISTS VS DROP?

Can someone tell me if there is any difference between

DROP IF EXISTS [TABLE_NAME]

DROP [TABLE_NAME]

I am asking this because I am using JDBC template in my MVC web application. If I use DROP [TABLE_NAME] the error said that Table exist. And if I use DROP IF EXISTS [TABLE_NAME] it says bad SQL grammar. Can some one help?

If no table with such name exists, DROP fails with error while DROP IF EXISTS just does nothing.

This is useful if you create/modifi your database with a script; this way you do not have to ensure manually that previous versions of the table are deleted. You just do a DROP IF EXISTS and forget about it.

Of course, your current DB engine may not support this option, it is hard to tell more about the error with the information you provide.

You forgot the table in your syntax:

drop table [table_name]

which drops a table.

Using

drop table if exists [table_name]

checks if the table exists before dropping it.
If it exists, it gets dropped.
If not, no error will be thrown and no action be taken.

It is not what is asked directly. But looking for how to do drop tables properly, I stumbled over this question, as I guess many others do too.

From SQL Server 2016+ you can use

DROP TABLE IF EXISTS dbo.Table

For SQL Server <2016 what I do is the following for a permanent table

IF OBJECT_ID('dbo.Table', 'U') IS NOT NULL 
  DROP TABLE dbo.Table; 

Or this, for a temporary table

IF OBJECT_ID('tempdb.dbo.#T', 'U') IS NOT NULL
  DROP TABLE #T; 

DROP TABLE IF EXISTS [table_name]

it first checks if the table exists, if it does it deletes the table while

DROP TABLE [table_name]

it deletes without checking, so if it doesn't exist it exits with an error