Magento – How to create a table in the database in Magento using install script

I am new to Magento, and I am trying to create a table in the database using an install script. THE WEB SITE IS HOSTED. I followed few tutorials, and they all look same. I followed every step, but the table is not created. Can some one tell me where I have gone wrong? I created the following file:

app/code/local/Sitepoint/Articles/etc/config.xml

It contains following code:

<global>
    <models>
        <articles>
            <class>Sitepoint_Articles_Model</class> <!-- Model class files -->     
            <resourceModel>articles_mysql4</resourceModel> <!--Resource model -->
        </articles>
        <articles_mysql4>
            <class>Sitepoint_Articles_Model_Mysql4</class>
            <entities>
                <articles>
                    <table>articles</table>  <!-- Db table name  -->
                </articles>
            </entities>
        </articles_mysql4>
    </models>
    <resources>  
        <articles_setup>
            <setup>
                <module>Sitepoint_Articles</module>
            </setup>
            <connection>
                <use>core_setup</use>
            </connection>
        </articles_setup>
        <articles_write>
            <connection>
                <use>core_write</use>
            </connection>
        </articles_write>
        <articles_read>
            <connection>
                <use>core_read</use>
            </connection>
        </articles_read>
    </resources>
</global>

Then I created following file:

app/code/local/Sitepoint/Articles/sql/articles_setup/mysql4-install-0.1.0.php

Which has the following code:

<?php
$installer = $this;
$installer->startSetup();
$installer->run("-- DROP TABLE IF EXISTS {$this->getTable('articles')};
CREATE TABLE {$this->getTable('articles')} (
      `articles_id` int(11) unsigned NOT NULL auto_increment,
      `title` varchar(255) NOT NULL default '',
      `short_desc` text NOT NULL default '',
      `long_desc` text NOT NULL default '',
      `status` tinyint(2) NOT NULL default '0',
      `created_time` datetime NULL,
      `update_time` datetime NULL,
      PRIMARY KEY (`articles_id`)
    ) ENGINE=InnoDB DEFAULT CHARSET=utf8;
    ");
    $installer->endSetup();
?>

I followed this tutorial => https://www.sitepoint.com/magento-install-upgrade-data-scripts-explained/ but the tables are not created. I tried few other tutorials, and they all provide the same way. Can someone help me?