SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '686d879c4c37a9e9403a19fad3d1c4c73b81493fa47fda0a86f3a5ec1af314af' 
  AND token = 'uzIBvCAfOk0WzoP3eQZ0zxGjCT9looH5Tol4av3oiys=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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