Redis additional features – transactions

introduce

• Allows the user to wrap multiple commands and then execute all of the wrapped commands in sequence at once
• During the execution of a transaction, the server will not interrupt the transaction to execute other command requests. Only after all the commands of the transaction are executed, the server will process other command requests
• Execute multiple commands at once and ensure that either all or none of the commands in the transaction are executed

Transaction command

• MULTIStart a new transaction After this command is executed, all commands sent by the client for the database or database keys are not executed immediately. Instead, they are placed in a transaction queue and QUEUED is returned to indicate that the command is QUEUED

  127.0.0.1:6379> multi 
  OK
  127.0.0.1:6379> set msg "hello world"
  QUEUED
  127.0.0.1:6379> expire msg 600
  QUEUED
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• DISCARDCancels the transaction, abandoning all commands in the transaction queue

  127.0.0.1:6379> discard
  OK
  127.0.0.1:6379> set msg "hello world"
  OK
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• EXECExecute all commands in the transaction queue in the order in which they are enqueued to the transaction queue. The return value of a command is a list of all the commands that are executed in the transaction queue

  127.0.0.1:6379> multi 
  OK
  127.0.0.1:6379>  set msg "hello world"
  QUEUED
  127.0.0.1:6379>  expire msg 600
  QUEUED
  127.0.0.1:6379> exec
  1) OK
  2) (integer) 1
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  Transaction error:

  127.0.0.1:6379> multi 
  OK
  127.0.0.1:6379>  set msg "hello world"
  QUEUED
  127.0.0.1:6379>  expire msg 1x
  QUEUED
  127.0.0.1:6379> exec
  (error) EXECABORT Transaction discarded because of previous errors.
  127.0.0.1:6379> get msg
  (nil)
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The difference between pipeline and transaction