SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'f187899a25e4acb24e55853e04d4f55ee522046b6064829d56fc64581ea9bdaa' 
  AND token = 'ryAdtjWeaQuz8L1Ez6ALyYf4bugcLjCqwcOZvrJ6sA8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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