Please Explain Drupal schema and drupal_write_record - drupal

Question

1) Where is the best place to populate a new database table when a module is first installed, enabled? I need to go and get some data from an external source and want to do it transparently when the user installs/enables my custom module.
I create the schema in {mymodule}_schema(), do drupal_install_schema({tablename}); in hook_install. Then I try to populate the table in hook_enable using drupal_write_record.
I confirmed the table was created, I get no errors when hook_enable executes, but when I query the new table, I get no rows back--it's empty.
Here's one variation of the code I've tried:
/**
* Implementation of hook_schema()
*/
function ncbi_subsites_schema() {
// we know it's MYSQL, so no need to check
$schema['ncbi_subsites_sites'] = array(
'description' => 'The base table for subsites',
'fields' => array(
'site_id' => array(
'description' => 'Primary id for site',
'type' => 'serial',
'unsigned' => TRUE,
'not null' => TRUE,
), // end site_id
'title' => array(
'description' => 'The title of the subsite',
'type' => 'varchar',
'length' => 255,
'not null' => TRUE,
'default' => '',
), //end title field
'url' => array(
'description' => 'The URL of the subsite in Production',
'type' => 'varchar',
'length' => 255,
'default' => '',
), //end url field
), //end fields
'unique keys' => array(
'site_id'=> array('site_id'),
'title' => array('title'),
), //end unique keys
'primary_key' => array('site_id'),
); // end schema
return $schema;
}
Here's hook_install:
function ncbi_subsites_install() {
drupal_install_schema('ncbi_subsites');
}
Here's hook_enable:
function ncbi_subsites_enable() {
drupal_get_schema('ncbi_subsites_site');
// my helper function to get data for table (not shown)
$subsites = ncbi_subsites_get_subsites();
foreach( $subsites as $name=>$attrs ) {
$record = new stdClass();
$record->title = $name;
$record->url = $attrs['homepage'];
drupal_write_record( 'ncbi_subsites_sites', $record );
}
}
Can someone tell me what I'm missing?

Answer 1

If ncbi_subsites_get_subsites() is not in the .install file, you need to include whatever file its in with your module. Otherwise, it's returning nothing, in which case try dumping $subsites and exiting.

Answer 2

I think the answer is that drupal_write_record is not meant for install or enable hooks. I think when enabling or installing, you have to write SQL. That is the impression I am getting from reading some posts that mention that the schema is not available in these hooks.

Answer 3

First of all (assuming Drupal 6), drupal_write_record() cannot be called from hook_install() because Drupal would not find the database schema defined from the module, which is still going to be installed, and enabled.
Instead you need to use db_query() function. (the comments are speaking of a way to include default data by prviding it to hook_schema() serialized, but i've found no documentation on this.)
However, would you be using (the development version of) Drupal 7, you want to look at the db_insert() function instead.