/**
* This function iterate over a large result set, only processing records in
* batches to keep the memory usage reasonable. After a batch has been collected,
* a reference to this object is passed to a callback function. That function
* will update any columns necessary. This function will the save the changes
* and start on a new batch.
*
* Callback function first argument must be a reference to a vB_DataManager_Multiple object.
* Additional arguments should be passed to this function in an array.
*
* @param string|resource A query result resource or a string containing the query to execute
* @param callback The function to call to make changes to the records
* @param integer Number of records to process in a batch
* @param array Any additional arguments to pass to the callback function
*/
function batch_iterate($records, $callback, $batch_size = 500, $args = array())
{
if (is_string($records)) {
$records = $this->dbobject->query_read($records);
}
$intargs = array(&$this);
foreach (array_keys($args) as $argkey) {
$intargs[] =& $args["{$argkey}"];
}
$counter = 0;
while ($record = $this->dbobject->fetch_array($records)) {
// this if is seperate because otherwise, if we had
// count($records) % $batch_size == 0, $this->children would be empty
// so we couldn't call post_save_once().
if ($counter % $batch_size == 0) {
$this->reset();
}
$this->add_existing($record);
$counter++;
if ($counter % $batch_size == 0) {
call_user_func_array($callback, $intargs);
$this->save(true, false);
}
}
$this->dbobject->free_result($records);
if ($this->children and $counter % $batch_size != 0) {
call_user_func_array($callback, $intargs);
$this->save(true, false);
}
$master =& $this->children[reset($this->primary_ids)];
if ($master) {
$master->post_save_once();
}
}
/**
* Fetches the existing data for the selected user
*
* @return array Array of [selector][property] = value
*/
function fetch_existing()
{
$usercss_result = $this->dbobject->query_read("\n\t\t\tSELECT * FROM " . TABLE_PREFIX . "usercss\n\t\t\tWHERE userid = " . $this->userid . "\n\t\t\tORDER BY selector\n\t\t");
$existing = array();
while ($usercss = $this->dbobject->fetch_array($usercss_result)) {
$existing["{$usercss['selector']}"]["{$usercss['property']}"] = $usercss['value'];
}
$this->dbobject->free_result($usercss_result);
return $existing;
}
/**
* Fetches the existing data for the selected user
*
* @return array Array of [selector][property] = value
*/
function fetch_existing()
{
$usercss_result = $this->dbobject->query_read("
SELECT * FROM " . TABLE_PREFIX . "usercss
WHERE userid = " . $this->userid . "
ORDER BY selector
");
$existing = array();
while ($usercss = $this->dbobject->fetch_array($usercss_result))
{
$existing["$usercss[selector]"]["$usercss[property]"] = $usercss['value'];
}
$this->dbobject->free_result($usercss_result);
return $existing;
}
