SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f4cb2a07982f443cc2186986569b4c482050ce2d690f338ef8fc7dbb0e89a121' 
  AND token = 'Y7gmrYfyIkdArPti3CBuWXbwblA+pKF3gXAO2WGJook=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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