SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '89d622888ec9c86a434ff6de80b98eb3c8258b766e67420b18e4e0df84171072' 
  AND token = 'INYnPix1VinWZNdcHzpMMJXoRl5nu9nsw+n5sARSGXk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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