How to run hook_update for the database Suppose we have a simple module with 3 files: test.info, test. install and test.module.
test.install
&lt;?php
function test_schema() {

    $schema['test'] = array(
        //fields
        'fields' =&gt; array(
            'id' =&gt; array(
                'type' =&gt; 'serial',
                'unsigned' =&gt; true,
                'not null' =&gt; true
                ),
            ),
        //additional properties
        'primary key' =&gt; array('id'),
        );

    return $schema;
}

When I install the module via the web interface, the table is created. Then I add hook_update:
function test_update_7100() {
    $spec = array(
        'type' =&gt; 'varchar',
        'description' =&gt; &quot;New Col&quot;,
        'length' =&gt; 20,
        'not null' =&gt; FALSE,
        );
    db_add_field( 'test', 'name', $spec);
}

Now I need to run the update function to modify the table. But I don't know where I can do it. Module is not present in &quot;Modules&quot; -&gt; &quot;Update&quot;.
You can run just drush updb -y on your site folder.