SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '09626671462844d79e8db9009fdfa462186143a5598f3b5c7019ee4b9f5714e8' 
  AND token = '2DdBCbWopF6IOFVrmjYp8shX+gkJpYURLSA2R343xK4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00047

JSON explain

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