SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5d18836313783743111032adfb6057fbb1aa5c59983243df5808cdfe53fb6c44' 
  AND token = '1VV+HkZX9MP56mQ7lkWxjljywbrWEt6oJAeklZu1Rag=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00048

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}