COMMAND GETKEYS

Introduction

The COMMAND GETKEYS command is used to extract the keys from a given command and its arguments in DiceDB. This command is particularly useful for analyzing the keys involved in a multi-key operation, such as MSET or DEL.

Syntax

COMMAND GETKEYS command arg [arg ...]

Parameters

Parameter	Description	Type	Required
command	The command for which keys need to be extracted.	String	Yes
arg	Arguments for the specified command.	String	Yes

Return values

Condition	Return Value
Command is successful	Array of keys
Error	An error is returned if the command fails.

Behavior

The COMMAND GETKEYS command parses the provided command and its arguments to extract the keys that are involved. It ensures that the correct keys are identified, regardless of the specific operation being performed. Internally, DiceDB understands the structure of each command using keyspecs and identifies which parameters are keys.

Errors

1. Arity Error for COMMAND GETKEYS

   • Error Message: (error) ERR wrong number of arguments for 'command|getkeys' command
   • Occurs when an incorrect number of arguments is provided for the COMMAND GETKEYS command.

2. Arity Error for command

   • Error Message: (error) ERR invalid number of arguments specified for command
   • Occurs when invalid number of arguments provided for command.

3. Invalid command specified

   • Error Message: (error) ERR invalid command specified
   • Occurs when the provided command is not a recognized DiceDB command.

4. No keys arguments

   • Error Message: (error) ERR the command has no key arguments
   • Occurs when the provided command does not accept any key arguments (ex. FLUSHDB).

Example Usage

Extracting keys from MSET command

127.0.0.1:7379> COMMAND GETKEYS MSET key1 value1 key2 value2
1) "key1"
2) "key2"

Extracting keys from DEL command

127.0.0.1:7379> COMMAND GETKEYS DEL key1 key2 key3
1) "key1"
2) "key2"
3) "key3"

Error: Arity Error for COMMAND GETKEYS

An arity error is thrown when the incorrect number of arguments is provided to the COMMAND GETKEYS command.

127.0.0.1:7379> COMMAND GETKEYS
(error) ERR wrong number of arguments for 'command|getkeys' command

Error: Arity Error for command name passed to COMMAND GETKEYS

An arity error is thrown when the incorrect number of arguments is provided to the command passed to COMMAND GETKEYS command.

127.0.0.1:7379> COMMAND GETKEYS MSET key1
(error) ERR invalid number of arguments specified for command

Error: Command Not Supported

An error is thrown when the specified command is not supported or recognized by the DiceDB server.

127.0.0.1:7379> COMMAND GETKEYS UNKNOWNCOMMAND key1
(error) ERR invalid command specified

Error: Command Does Not Accept Key Arguments

An error is thrown when attempting to retrieve keys for a command that does not accept any key arguments.

127.0.0.1:7379> COMMAND GETKEYS FLUSHDB
(error) ERR The command has no key arguments