SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '87b78751a97ec68d94221b5c3f74ae07e0ad1ec12e55bcb8ba8443381a8cfcda' 
  AND token = 'OOzgq8WJwbSunWTbJzhAZ40WMRH+VxkMLrZslrtG/8w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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