/src/php/caching/caching.php

<?php
/* Copyright 2012 Aditi Muralidharan. See the file "LICENSE" for the full license governing this code. */

/*******************************************************************************
caching.php

Utilities for caching the the sentences,
phrases, and documents that match a query.
*******************************************************************************/

include_once "../util.php";
$wordseer_instance = getGetParam('instance');
$path = '../../../instances/'.$wordseer_instance.'/config.php';
include_once $path;

//Query parameters
$gov = getGetParam('gov');
$govtype = getGetParam('govtype');
$dep = getGetParam('dep');
$deptype = getGetParam('deptype');
$relation = getGetParam('relation');
$collection = getGetParam('collection');
$statistics = getGetParam('statistics');
$start = getGetParam('start');
$limit = getGetParam('limit');
$metadata = decodeGetJson('metadata');
$searches = (Array) decodeGetJson('search');
$phrases = decodeGetJson('phrases');
$timing = getGetParam('timing');

include_once "../grammaticalsearch/get-search-results.php";
include_once '../document/get-metadata.php';
include_once '../subsets/read.php';
include_once "../phrases/get-phrases.php";

if (strstr($_SERVER['REQUEST_URI'], 'caching.php')) {
	makeCacheTables();
	if (getGetParam('clear')) {
		dispatch_clear_query_cache(getGetParam('query_id'));
	} else {
		dispatch_caching($searches, $collection, $metadata, $phrases);
	}
}

function dispatch_clear_query_cache($query_id) {
	$sql = "DELETE FROM cached_filtered_sent_ids WHERE query_id < ($query_id-100);";
	mysql_query($sql) or die (mysql_error()." on: 
		<br> $sql caching.php l 46");
}

/** Creates tables to cache the results of applying the filters for this query.
*/
function makeCacheTables() {
	$sql = "CREATE TABLE IF NOT EXISTS `cached_filtered_sent_ids` (
		`id` int(11) NOT NULL DEFAULT '0',
		`document_id` int(11) NOT NULL DEFAULT '0',
		`num_matched` int(11) NOT NULL DEFAULT '1',
		`num_searches_matched` int(11) NOT NULL DEFAULT '0',
		`query_id` int NOT NULL DEFAULT '-1',
		PRIMARY KEY (`query_id`, `id`),
		KEY `num_matched` (`query_id`, `num_matched`, `id`),
		KEY `num_searches_matched` (`query_id`, `num_searches_matched`, `id`)
	) ENGINE=MyISAM DEFAULT CHARSET=utf8";
	mysql_query($sql) or die (mysql_error()." on: 
		<br> $sql caching.php l 54");
}

/** Does the filtering operations necessary for the
query and prints out a new query ID.
*/
function dispatch_caching($searches, $collection, $metadata, $phrases) {
	global $timing;
	global $cache_results;
	global $search_result_union;
	$search_result_union = (count($searches)  > 1);
	$cache_results = true;
	global $query_id;
	$query_id = getNextQueryID();
	dispatch_clear_query_cache($query_id);
	$gov = '';
	$dep = '';
	$relation = '';
	$govtype = 'word';
	$deptype = 'word';
	if (count($searches) > 0) {
		foreach ($searches as $search) {
			if ($search_result_union) {
				global $num_search_conditions;
				global $num_filter_conditions;
				$num_search_conditions = 0;
				$num_filter_conditions = 0;
			}
			$gov = $search['gov'];
			$dep = $search['dep'];
			$relation = $search['relation'];
			$govtype = $search['govtype'];
			$deptype = $search['deptype'];
			if ($relation == "") {
				getSentenceSearchResults($gov, $govtype, $collection, 
					$metadata, $phrases);
			} else {
				getDependencySentenceResults($gov, $govtype, $dep, $deptype, 
					$relation, $collection, false, $metadata, $phrases);
			}
			if ($timing) displayFilterStatistics();
		}
	} else {
		getSentenceSearchResults($gov, $govtype, $collection, $metadata,
			$phrases);
	}
	
	echo json_encode(array(
		'ok'=>true,
		'query_id'=>$query_id
		));
}

function getNextQueryID() {
	$sql = "CREATE TABLE IF NOT EXISTS `query_cache`(
		`query_id` int NOT NULL auto_increment,
		PRIMARY KEY (`query_id`)) ENGINE=MyISAM DEFAULT CHARSET=utf8";
	mysql_query($sql) or die (mysql_error()." on: 
		<br> $sql <br> at caching/caching.php l 104");
	$sql = "SELECT max(query_id) as max from query_cache;";
	$result = mysql_query($sql) or die (mysql_error()." on: 
		<br> $sql <br> at caching/caching.php l 107");
	$query_id = 0;
	while($row = mysql_fetch_assoc($result)) {
		$query_id = $row['max'];
	}
	$query_id += 1;
	$sql = "INSERT INTO query_cache (query_id) VALUES ($query_id);";
	mysql_query($sql) or die (mysql_error()." on: 
		<br> $sql <br> at caching/caching.php l 115");
	return $query_id;	
}
?>