Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f39639dc00dfe08ebda77b0e3124404a460f10f5a7c1b46ab7be047a90f6e394' 
  AND token = 'RcNwEQPhnsqEzmK3Rm6FmqOTGxtmvoEotauI5RPN7qI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}