SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c532fb02eb93137b493595ef65f08433bba024b4ffa9b834a17ec81878998278' 
  AND token = 'ryEVYiUKx3T2mqcu+etoc1VY8//8RDs7jj2J78smIPk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00015

JSON explain

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