Skip to main content

Difference Between TRUNCATE, DELETE and DROP commands

1.DELETE
  • The DELETE command is used to remove rows from a table. 
  • A WHERE clause can be used to  remove some rows. 
  • If no WHERE condition is specified, all rows will be removed. 
  • After performing a DELETE operation you need to COMMIT or ROLLBACK the transaction to make the change permanent or to undo it.
  • Note that this operation will cause all DELETE triggers on the table to fire.
2.TRUNCATE
  • TRUNCATE removes all rows from a table. 
  • No triggers will be fired. 
  • Not able to perform ROLLBACK operation.
  • TRUNCATE is faster then DELETE and doesn't use as much undo space as a DELETE.
3.DROP
  • The DROP command removes a table from the database.
  •  All the tables' rows, indexes and privileges will also be removed. 
  • No DML triggers will be fired. 
  • Not able to perform ROLLBACK operation.
SOME MORE DIFFERENCES

DROP and TRUNCATE are DDL commands, whereas DELETE is a DML command. 
DELETE operations can be ROLLBACK (undone), while DROP and TRUNCATE operations cannot be ROLLBACK.
Labels:

Comments

Post a Comment

Popular posts from this blog

How to make the email Address Dummy in Oracle Database?

How to make the email Address Dummy in Oracle Database? Query to make the email Address as dummy, update <tablename> set <Columnname> = '@' || <Columnname> where <Columnname>  is not null; Query to Remove the email Address as dummy, update <tablename> set <Columnname>= substr(<Columnname>,2,length(<Columnname>)) where <Columnname> is not null;
Post a Comment
Read more

Upgrading Windows Server 2008 R2 with a command-line tool using DISM

Windows Server 2008 R2 includes a command-line tool called the Deployment Image Servicing and Management tool, or DISM. It's functionally equivalent to the Windows Anytime Upgrade feature in client versions of Windows. You can run it from an elevated command prompt. To determine the currently installed edition: DISM /online /Get-CurrentEdition To determine the editions you can upgrade to: DISM /online /Get-TargetEditions To actually perform an upgrade: DISM /online /Set-Edition:<edition ID> /ProductKey:XXXXX-XXXXX-XXXXX-XXXXX-XXXXX
Post a Comment
Read more

List of FTP commands for the Microsoft command-line FTP client

Command-line options As you're starting the program from a DOS prompt: ftp [-v] [-d] [-i] [-n] [-g] [-s:filename] [-a] [-w:windowsize] [computer] -v  - Suppresses  verbose  display of remote server responses. -n  - Suppresses auto-login upon initial connection. -i  - Turns off interactive  prompting  during multiple file transfers. -d  - Enables  debugging , displaying all ftp commands passed between the client and server. -g  - Disables filename  globbing , which permits the use of wildcard chracters in local file and path names. -s:filename  - Specifies a text file containing ftp commands; the commands will automatically run after ftp starts. No spaces are allowed in this parameter. Use this switch instead of redirection (>). -a  - Use any local interface when binding data connection. -w:windowsize  - Overrides the default transfer buffer size of 4096. computer  - Specifies the computer name o...
Post a Comment
Read more