Skip to content
DiceDB

GETDEL

The GETDEL command in DiceDB is used to retrieve the value of a specified key and then delete the key from the database. This command is useful when you need to fetch a value and ensure that it is removed from the database in a single atomic operation.

Syntax

Terminal window
GETDEL key

Parameters

ParameterDescriptionTypeRequired
keyThe key whose value you want to retrieve and delete.StringYes

Return values

ConditionReturn Value
Key existsString: The command returns the value associated with the key.
Key does not existnil: The command returns nil.

Behaviour

  • If the specified key exists, GETDEL retrieves its value and then deletes the key from the database.
  • The retrieved value is returned to the client.
  • If the key does not exist, GETDEL returns nil and no deletion is performed.

Errors

  1. Wrong Type Error:

    • Error Message: ERROR WRONGTYPE Operation against a key holding the wrong kind of value
    • Occurs if the key exists but is not a string (e.g., it is a list, set, hash, etc.).

  2. Syntax Error:

    • Error Message: ERROR wrong number of arguments for 'getdel' command
    • Occurs if the command is called without the required parameter.

Example Usage

Retreive and Delete an Existing Key

Setting a key mykey with the value "Hello, World!" and then using GETDEL to retrieve and delete it.

Terminal window
127.0.0.1:7379> SET mykey "Hello, World!"
OK
127.0.0.1:7379> GETDEL mykey
"Hello, World!"
127.0.0.1:7379> GET mykey
(nil)

Using GETDEL on a Non-Existent Key

Trying to retrieve and delete a key nonexistingkey that does not exist.

Terminal window
127.0.0.1:7379> GETDEL nonexistingkey
(nil)
  • The key nonexistingkey does not exist in the database.
  • The GETDEL command returns nil since the key is not found.

Using GETDEL on a Key with a Different Data Type

Setting a key mylist as a list and then trying to use GETDEL, which is incompatible with non-string data types.

Terminal window
127.0.0.1:7379> LPUSH mylist "item1"
(integer) 1
127.0.0.1:7379> GETDEL mylist
ERROR WRONGTYPE Operation against a key holding the wrong kind of value
  • The key mylist is a list, not a string.
  • The GETDEL command raises a WRONGTYPE error because it expects the key to be a string. (error) WRONGTYPE Operation against a key holding the wrong kind of value