Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6d087c204cd0f05ed6d4b681aa2b561adfba1d9e034cbf221a55f5a62bad9cd6' 
  AND token = 'NrmF4y/VQaxqMJnR/S+buN3yFTdWRqORkqE/ZeNgtWU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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