SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '190e2d38c668feeb09311429727d7b156736e00112dc389e406c43a3a57c7154' 
  AND token = 'i6wnNhxM2kLhzWmcNySvk0dQ0RsIENGYp4yN3VrIaQs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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