SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '23434b1af1a798524a2b3d3dfdc23b9c787aabd98f9f697e945d044a6ec7a209' 
  AND token = 'jM2//jRgP6J2NfrobZjnotmGYMTB6Gcbtwr++xCGl/M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00114

JSON explain

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