drupal/includes/database.mysql.inc

293 lines
7.2 KiB
PHP

<?php
// $Id$
/**
* @file
* Database interface code for MySQL database servers.
*/
/**
* @ingroup database
* @{
*/
/**
* Initialize a database connection.
*
* Note that you can change the mysql_connect() call to mysql_pconnect() if you
* want to use persistent connections. This is not recommended on shared hosts,
* and might require additional database/webserver tuning. It can increase
* performance, however, when the overhead to connect to your database is high
* (e.g. your database and web server live on different machines).
*/
function db_connect($url) {
$url = parse_url($url);
// Allow for non-standard MySQL port.
if (isset($url['port'])) {
$url['host'] = $url['host'] .':'. $url['port'];
}
$connection = mysql_connect($url['host'], $url['user'], $url['pass']) or die(mysql_error());
mysql_select_db(substr($url['path'], 1)) or die('unable to select database');
return $connection;
}
/**
* Runs a basic query in the active database.
*
* User-supplied arguments to the query should be passed in as separate parameters
* so that they can be properly escaped to avoid SQL injection attacks.
*
* @param $query
* A string containing an SQL query.
* @param ...
* A variable number of arguments which are substituted into the query using
* printf() syntax.
* @return
* A database query result resource, or FALSE if the query was not executed
* correctly.
*/
function db_query($query) {
$args = func_get_args();
$query = db_prefix_tables($query);
if (count($args) > 1) {
if(is_array($args[1])){
$args1 = array_map('check_query', $args[1]);
$nargs = array_merge(array($query), $args1);
}
else {
$nargs = array_map('check_query', $args);
$nargs[0] = $query;
}
return _db_query(call_user_func_array('sprintf', $nargs));
}
else {
return _db_query($query);
}
}
/**
* Debugging version of db_query().
*
* Echoes the query to the browser.
*/
function db_queryd($query) {
$args = func_get_args();
$query = db_prefix_tables($query);
if (count($args) > 1) {
if(is_array($args[1])){
$args1 = array_map('check_query', $args[1]);
$nargs = array_merge(array($query), $args1);
}
else {
$nargs = array_map('check_query', $args);
$nargs[0] = $query;
}
return _db_query(call_user_func_array('sprintf', $nargs), 1);
}
else {
return _db_query($query, 1);
}
}
/**
* Helper function for db_query().
*/
function _db_query($query, $debug = 0) {
global $active_db;
global $queries;
if (variable_get('dev_query', 0)) {
list($usec, $sec) = explode(' ', microtime());
$timer = (float)$usec + (float)$sec;
}
$result = mysql_query($query, $active_db);
if (variable_get('dev_query', 0)) {
list($usec, $sec) = explode(' ', microtime());
$stop = (float)$usec + (float)$sec;
$diff = $stop - $timer;
$queries[] = array($query, $diff);
}
if ($debug) {
print '<p>query: '. $query .'<br />error:'. mysql_error() .'</p>';
}
if (!mysql_errno()) {
return $result;
}
else {
trigger_error(mysql_error() ."\nquery: ". htmlspecialchars($query), E_USER_ERROR);
}
}
/**
* Fetch one result row from the previous query as an object.
*
* @param $result
* A database query result resource, as returned from db_query().
* @return
* An object representing the next row of the result. The attributes of this
* object are the table fields selected by the query.
*/
function db_fetch_object($result) {
if ($result) {
return mysql_fetch_object($result);
}
}
/**
* Fetch one result row from the previous query as an array.
*
* @param $result
* A database query result resource, as returned from db_query().
* @return
* An associative array representing the next row of the result. The keys of
* this object are the names of the table fields selected by the query, and
* the values are the field values for this result row.
*/
function db_fetch_array($result) {
if ($result) {
return mysql_fetch_array($result, MYSQL_ASSOC);
}
}
/**
* Determine how many result rows were found by the preceding query.
*
* @param $result
* A database query result resource, as returned from db_query().
* @return
* The number of result rows.
*/
function db_num_rows($result) {
if ($result) {
return mysql_num_rows($result);
}
}
/**
* Return an individual result field from the previous query.
*
* Only use this function if exactly one field is being selected; otherwise,
* use db_fetch_object() or db_fetch_array().
*
* @param $result
* A database query result resource, as returned from db_query().
* @param $row
* The index of the row whose result is needed.
* @return
* The resulting field.
*/
function db_result($result, $row = 0) {
if ($result && mysql_num_rows($result) > $row) {
return mysql_result($result, $row);
}
}
/**
* Determine whether the previous query caused an error.
*/
function db_error() {
return mysql_errno();
}
/**
* Return a new unique ID in the given sequence.
*
* For compatibility reasons, Drupal does not use auto-numbered fields in its
* database tables. Instead, this function is used to return a new unique ID
* of the type requested. If necessary, a new sequence with the given name
* will be created.
*/
function db_next_id($name) {
$name = db_prefix_tables($name);
db_query('LOCK TABLES {sequences} WRITE');
$id = db_result(db_query("SELECT id FROM {sequences} WHERE name = '%s'", $name)) + 1;
db_query("REPLACE INTO {sequences} VALUES ('%s', %d)", $name, $id);
db_query('UNLOCK TABLES');
return $id;
}
/**
* Determine the number of rows changed by the preceding query.
*/
function db_affected_rows() {
return mysql_affected_rows();
}
/**
* Runs a limited-range query in the active database.
*
* Use this as a substitute for db_query() when a subset of the query is to be
* returned.
* User-supplied arguments to the query should be passed in as separate parameters
* so that they can be properly escaped to avoid SQL injection attacks.
*
* @param $query
* A string containing an SQL query.
* @param ...
* A variable number of arguments which are substituted into the query using
* printf() syntax.
* @param $from
* The first result row to return.
* @param $count
* The maximum number of result rows to return.
* @return
* A database query result resource, or FALSE if the query was not executed
* correctly.
*/
function db_query_range($query) {
$args = func_get_args();
$count = array_pop($args);
$from = array_pop($args);
if (count(func_get_args()) > 3) {
$args = array_map('check_query', $args);
$query = db_prefix_tables($query);
$args[0] = $query;
$query = call_user_func_array('sprintf', $args);
}
else {
$query = func_get_arg(0);
$query = db_prefix_tables($query);
}
$query .= ' LIMIT '. $from .', '. $count;
return _db_query($query);
}
/**
* Returns a properly formatted Binary Large OBject value.
*
* @param $data
* Data to encode.
* @return
* Encoded data.
*/
function db_encode_blob($data) {
return $data;
}
/**
* Returns text from a Binary Large OBject value.
*
* @param $data
* Data to decode.
* @return
* Decoded data.
*/
function db_decode_blob($data) {
return $data;
}
/**
* @} End of "ingroup database".
*/
?>