How do I automatically update database tables when changing custom entity fields

Question

New Drupal Developer here.

I am currently working on a inventory management module for a friend. And I ran into a bit of a snag with Custom Entities in Drupal 8.

I have a custom "Customer" entity content type which stores various bits of information about the customer, first name, last name, a number which we assign each customer, etc...

When I added a new field post-module-install, after running update.php, cron, etc... The new field was never added to the existing SQL table.

I am wondering if there is something I'm missing, like a way to force update the database without having to manually add the new table.

Here is the new field I added.

$fields['l_number'] = BaseFieldDefinition::create('string')
        ->setLabel(t('L#'))
        ->setDescription(t('The Customer\'s L Number.'))
        ->setSettings(array(
            'default_value' => '',
            'max_length' => 8,
            'text_processing' => 0,
        ))
        ->setDisplayOptions('view', array(
            'label' => 'above',
            'type' => 'string',
            'weight' => -7,
        ))
        ->setDisplayOptions('form', array(
            'type' => 'string',
            'weight' => -7,
        ))
        ->setDisplayConfigurable('form', TRUE)
        ->setDisplayConfigurable('view', TRUE);

Answer 1

Using hook_update_N() as linked in @cilefen's answer is way to do it when you have an existing sites with data and want it to make easier for users to run your updates.

If you're doing the initial development on a development environment, then I'd consider just re-installing the module (that's pretty fast with drush pmu -y module; drush en -y module).

You can also try drush entity-updates. If you don't have/know drush yet, you're missing out: https://github.com/drush-ops/drush

Answer 2

There are published examples using hook_update_n().