SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ee07634b338d8bc903ae5aafd1aac2c53feb743e1d604e64ebc17f1a7a85c68d' 
  AND token = '7CvPpXP3jq6gyAfs7XbFnAeEOPVlgZBvzMQj0Q3MNpg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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