Creating a form to submit data into wordpress database

Question

I have been trying to come up with some way to get a html form i made on a wordpress page to take the information entered and send it to custom tables in the wordpress database. I have tried calling a custom php script and writing code in the page itself and i cannot not figure out how to get it to work. I am going crazy trying to figure this out, I am about to give up. Any suggestions on where to start looking, enough i have been searching for a week, would be great.

I have tried using mysqli_connection but i keep getting issue connecting where i put (mysite.com,user,pass,db); and i get another error "cannot connect "user@anotherunknownsite.com" i have a shared ip so i wonder if it is connecting to this other site, which has NO reference in my code. I tired using local host instead of my site but nothing works.

This code tries to get some data off the db but nothing happens, same as b4 where mysite.com shows a error cant connect to user@randomsite.com and localhost doesnt work.

 <?php
    $con=mysqli_connect("mysite.com","user","pass","db");
    // Check connection
    if (mysqli_connect_errno()) {
      echo "Failed to connect to MySQL: " . mysqli_connect_error();
    }

    $result = mysqli_query($con,"SELECT * FROM Liquor_Type");

    while($row = mysqli_fetch_array($result)) {
      echo $row['lq_name'] . " " . $row['description'];
      echo "<br>";
    }

    mysqli_close($con);
    ?>

my form

<form  action = "setLQType.php" method="post">
Add a New Liquor Type</br></br>
<p>Name: <input type="text" name="name"/></p>
<p>Description <input type="text" name="description"/></p>
----------------------------------------------
<input type="submit" name="Submit"/>
</form>
</br>

The setLQType php file, which is in the main wordpress dictionary. It will got to the file but do nothing.

<?php
$con=mysqli_connect("mysite.com","user","pass","db_name");
// Check connection
if (mysqli_connect_errno()) {
  echo "Failed to connect to MySQL: " . mysqli_connect_error();
}
$name = mysqli_real_escape_string($con, $_POST['name']);
$description = mysqli_real_escape_string($con, $_POST['description']);

$sql="INSERT INTO Liquor_Type(lq_name, description)
VALUES ('$name ', '$description)";

if (!mysqli_query($con,$sql)) {
  die('Error: ' . mysqli_error($con));
}
echo "1 record added";

mysqli_close($con);
?>

Updated insert page... setLiquorType.php in website.com/setLiquorType.php

<?php 
$global $wpdb;
$name = $_POST['name'];
$description = $_POST['description'];
$table_name = $wpdb->prefix . "wp_Liquor_Type";
$wpdb->insert($table_name, array(
                            'lq_name' => $name,
                            'description' => $description
                            ));
?>

Answer 1

I recommend to use WP functions to do the work. You need the global object $wpdb to use them. For insert try with $wpdb->insert($table, $array).

You can define a shortcode that you put in functions.php or make a little plugin for this. In the same function yo can paint the form and try to get the data from it (thought I prefer to get the data first and paint the form the last)

Here you have a code that works:

<?php
if( $_POST['name'] != '' && is_email($_POST['email']) && wp_verify_nonce( $_POST['aspirante_nonce'], 'graba_aspirante')) {
    $table = 'Liquor_Type';
    $nombre = sanitize_text_field($_POST['nombre']);
    $correo = $_POST['correo'];
    $web = esc_url($_POST['web']);
    $created_at = date('Y-m-d H:i:s');

    $wpdb->insert(
        $table,
        array(
            'name' => $name,
            'email' => $email,
            'web' => $web,
            'created_at' => $created_at,
        )
    );
    echo "<p>Your data has been recorded. Thanks!<p>";   
} else {
    echo "<p>There was an error. Try again, please!<p>";   
}
ob_start();
?>
<form action="<?php get_the_permalink(); ?>" method="post" id="my_form">
    <?php wp_nonce_field('save_it', 'form_nonce'); ?>
    <div class="form-input">
        <label for="name">Name</label>
        <input type="text" name="name" id="name" required>
    </div>
    <div class="form-input">
        <label for='email'>Email</label>
        <input type="email" name="email" id="email" required>
    </div>
    <div class="form-input">
        <label for="web">Web</label>
        <input type="text" name="web" id="web">
    </div>
    <div class="form-input">
        <input type="submit" value="Submit">
    </div>
</form>
<?php

return ob_get_clean();

Answer 2

Posting works like this:

global $wpdb;

$name = sanitize_text_field(  $_POST['name']);
$lq_name = sanitize_text_field( $_POST['lq_name']);
$description = $_POST['description'];
$table_name = $wpdb->prefix . "Liquor_Type";
$wpdb->insert( $table_name, array(
    'liquor_name' => $liquor_name,
    'description' => $description
) );

Your mysql connection is available in the var $wpdb

global $wpdb; 

                    $sql="SELECT * FROM Liquor_Type";

                    $row = $wpdb->get_results($sql);                   
                    foreach ($row as $data)
                    {
                     echo $data->lq_name. " " . $data->description;
                       echo "<br>";
                    }