SQL

<?php
include "../../Connections/conecta_site.php";
if (!function_exists("GetSQLValueString")) {
function GetSQLValueString($theValue, $theType, $theDefinedValue = "", $theNotDefinedValue = "")
{
  if (PHP_VERSION < 6) {
    $theValue = get_magic_quotes_gpc() ? stripslashes($theValue) : $theValue;
  }

  //Inicia aqui
  $theValue = mysqli_real_escape_string($conecta, $theValue);
  //Termina aqui

  switch ($theType) {
    case "text":
      $theValue = ($theValue != "") ? "'" . $theValue . "'" : "NULL";
      break;
    case "long":
    case "int":
      $theValue = ($theValue != "") ? intval($theValue) : "NULL";
      break;
    case "double":
      $theValue = ($theValue != "") ? doubleval($theValue) : "NULL";
      break;
    case "date":
      $theValue = ($theValue != "") ? "'" . $theValue . "'" : "NULL";
      break;
    case "defined":
      $theValue = ($theValue != "") ? $theDefinedValue : $theNotDefinedValue;
      break;
  }
  return $theValue;
}
}

$editFormAction = $_SERVER['PHP_SELF'];
if (isset($_SERVER['QUERY_STRING'])) {
  $editFormAction .= "?" . htmlentities($_SERVER['QUERY_STRING']);
}

if ((isset($_POST["MM_insert"])) && ($_POST["MM_insert"] == "form")) {
  $insertSQL = sprintf("INSERT INTO newsletter (nome, email) VALUES (%s, %s)",
                       GetSQLValueString($_POST['nome'], "text"),
                       GetSQLValueString($_POST['email'], "text"));

  //Inicia aqui
  $db_select = mysqli_select_db($STRING_DE_CONEXAO_COM_O_BANCO, "NOME_DO_SEU_BANCO");
  //Termina aqui

  //Inicia aqui
  $Result1 = mysqli_query($insertSQL, $db_select) or die(mysqli_error());
  //Termina aqui

  $insertGoTo = "newsletter.php";
  if (isset($_SERVER['QUERY_STRING'])) {
    $insertGoTo .= (strpos($insertGoTo, '?')) ? "&" : "?";
    $insertGoTo .= $_SERVER['QUERY_STRING'];
  }
  header(sprintf("Location: %s", $insertGoTo));
}
?>

<link href="css/estilos.css" rel="stylesheet" type="text/css" />

<form method="POST" name="form" action="<?php echo $editFormAction; ?>"POST" >
<ul>
<li> <label class="name_newsletter" for="name">Nome:</label> <input type="nome" class="news_footer_name" name="nome"  id="nome"  maxlength="100" /></li>

<li> <label class="email_newsletter" for="email">E-mali:</label> <input type="email" class="news_footer_mail" name="email" id="email" maxlength="100"/></li>

<input class="btn_newsletter" type="submit" value="Cadastrar" id="btnSend">
<input type="hidden" name="MM_insert" value="newsletter" />
<input type="hidden" name="MM_update" value="newsletter" />
<input type="hidden" name="MM_insert" value="form" />
</form>
</ul>