Schema API looks a good option for generating tables in a DB independent fashion. But I could not find solutions to some issues (like how to specify the Engine for MySql, or foreign key constraints or creating Stored Procedures & Functions).

Looks like this has to be done by getting a sql script executed. But the above doc does not detail how to get a Sql script executed during install/uninstall?

Can somebody document this aspect a bit??

Interesting article about using an install file to store frontend interactions of a Drupal project:
http://sachachua.com/wp/2009/04/23/drupal-staging-and-deployment-tips-it...

If you are writing the .install file LAST (ie after module has been activated), you need to make sure you disable the module and uninstall it first. Be careful though, as uninstalling removes everything in the table. Then by reactivating it, it should create the new table.

My suggestion before uninstalling is to rename the table name ie instead of 'node' name it to like 'node1'. You will get an error message, but at least it will not drop the entire 'node' table

Hi everyone, I want to support multi-site setup for my module. Is there a function to get
the current db_prefix? In Drupal 6 I can use global $db_prefix within a hook
but in Drupal 7 it's blank. I want to use db_prefix in hook_schema in Drupal
7. Any function or variable that holds the prefix?

There's nothing to worry about $db_prefix in the hook_schema because Drupal 7 will automatically handle the prefix of the current Drupal site. However, I want to use $db_prefix in another hook and other functions. What's the function for getting the prefix? I know that we can get it from the globals $databases['default']['default']['prefix'] but I don't like to use that.

Is there any way to make the _install fail, for instance when a query fails or some other error occurs during installation, resulting in the module not being installed and an error message shown?

Your hook_schema should always return the updated schema. In other words: If you add a table in hook_update_N, also add it to hook_schema.

For those who using Drupal 7 but following this guide you may be seeing this error when your module installs: DatabaseSchemaObjectExistsException: Table already exists

The Drupal 7 page describing how to build .install files recommends coming to this page (originally for the D6 version) for instructions. One big difference is that there's no need to use the drupal_install_schema function. Drupal will automatically install the schema you've defined, so calling the install function is basically trying to install the database twice.

I hope that helps someone.

I have created a custom table within a module for a content type which was created. I was able to add content and when I search the node table I could find the nid and the vid fields. How do i find other fields in the custom table, please assist.

The .install file for the Conference module doesn't work - it is a D5 module and was not fully updated for D6 it seems. If you create the tables in MySql it works perfectly, so I just want to fix the .install file. This is what I have written, but I get an error message on Function conference_install.

As this was a D5 module, I dont know if another file can be influencing this installation.

<?php
function conference_schema() {
$schema['conference'] = array(
    'description' => t('The base table for conference.'),
    'fields' => array(
      'pnid' => array(
        'description' => t('The primary identifier for a conference.'),
        'type' => 'serial',
        'unsigned' => TRUE,
        'not null' => TRUE),
      'pvid' => array(
        'description' => t('The current {node_revisions}.vid version identifier.'),
        'type' => 'int',
        'unsigned' => TRUE,
        'not null' => TRUE,
        'default' => 0),
      'ruid' => array(
        'description' => t('RUID'),
        'type' => 'int',
        'length' => 10,
        'not null' => TRUE,
        'default' => '0'),
      'rnid' => array(
        'description' => t('RNID'),
        'type' => 'int',
        'length' => 10,
        'not null' => TRUE,
        'default' => '0'),
      'comment1' => array(
        'description' => t('Comment for Organiser only.'),
        'type' => 'varchar',
        'length' => 255,
        'not null' => TRUE,
        'default' => ''),
      'comment2' => array(
        'description' => t('Comment for Author.'),
        'type' => 'varchar',
        'length' => 255,
        'not null' => TRUE,
        'default' => ''),        
      'status' => array(
        'description' => t('The Status.'),
        'type' => 'int',
        'length' => 10,
        'not null' => TRUE,
        'default' => '0'),
     ),   
    'primary key' => array('pnid','ruid','pvid'),
);

$schema['conference_decision'] = array(
    'description' => t('The acceptance of the paper.'),
    'fields' => array(
      'pnid' => array(
        'description' => t('The primary identifier for a decision.'),
        'type' => 'serial',
        'unsigned' => TRUE,
        'not null' => TRUE),
      'decision' => array(
        'description' => t('Type of Decision (abstract or full paper).'),
        'type' => 'int',
        'unsigned' => TRUE,
        'not null' => TRUE,
        'default' => 0),

      'feedback' => array(
        'description' => t('Feedback for decision.'),
        'type' => 'varchar',
        'length' => 255,
        'not null' => TRUE,
        'default' => ''),
),   
    'primary key' => array('pnid'),

);
return $schema;
}
/*
* Implementation of hook_install()
*/

function conference_install() {
  // Create my tables.
  drupal_install_schema('conference');  // I get an error 'unexpected T_STRING, expecting ')' in ..conference\conference.install' 
}

function conference_uninstall() {
  // Drop my tables.
  //
  //
  //
  drupal_uninstall_schema('conference');
}
?>