SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2636f8769b11640c8d1e239d3861e787a6976c368bf71c122d72aaca5d47aad5' 
  AND token = 'Lnq9oa1A7sSIKl4mYLbLow2avB5kzqOAp8T+bRKEImo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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