how to show database content in wordpress post

Question

I'm a beginner for WordPress. I have a database app written in PHP and MySQL and I need to convert it to WordPress and also I what to post the database rows info by shortcode were id="x" like:

[plugin id="1"]

It is a small database. Just give me a small demo code or link plz. I need it and help me to learn WordPress.

Answer 1

For the sake of the example, I'll assume you to have copied the relevant Table to the WordPress DB, to have named it wp_my_xtra_table and it to contain 3 columns (id,num_val,str_val).

function wpse106832_shortcode_demo( $atts ) {
    global $wpdb;

    extract( shortcode_atts( array(
        'id' => 1
    ), $atts ) );

    $table_row = $wpdb->get_row(
        'SELECT * ' .
        'FROM ' . $wpdb->prefix . 'my_xtra_table ' .
        'WHERE id = ' . $id, ARRAY_A
    );

    if ( ! empty( $table_row ) ) {
        return '<table><tr>' .
                 '<th>ID</th>' .
                 '<th>Numeric Value</th>' .
                 '<th>String Value</th>' .
             '</tr>' .
             '<tr>' .
                 '<td>' . $table_row['id'] . '</td>' .
                 '<td>' . $table_row['num_val'] . '</td>' .
                 '<td>' . $table_row['str_val'] . '</td>' .
             '</tr></table>';
    } else {
        return '<p>Nothing found.</p>';
    }
}
add_shortcode( 'wpse106832', 'wpse106832_shortcode_demo' );

With the above, [wpse106832 id=3] will display your third database entry.

Related Reading

• The Shortcode API
• add_shortcode
• The WPDB class