【发布时间】：2014-02-11 01:10:34
【问题描述】：
我正在尝试修改 DataTables 1.10（目前处于测试阶段的最新版本）的默认服务器端脚本，以允许表连接和自定义“WHERE”条件。 'WHERE' 条件可以正常工作，就像我之前所做的那样，但是，我在表连接方面遇到了一些问题。我早些时候取得了一些进展（我不再在 firebug 中收到任何错误），但是每行的所有列都返回一个空值作为响应。换句话说，我的表格显示在页面上，每一行都是空列。
我已经尝试过数据表论坛，但运气不佳。为简单起见，我没有包含所有内容，但也包含了服务器端 php 处理脚本和 ssp.class.php 脚本。
processing.php：
// DB table to use
$table = "`users`";
// Join condition
$myJoin = "LEFT JOIN `security` ON `users`.`user_id` = `security`.`user_id`";
// Table's primary key
$primaryKey = "`users`.`user_id`";
// Array of database columns which should be read and sent back to DataTables.
// The `db` parameter represents the column name in the database, while the `dt`
// parameter represents the DataTables column identifier. In this case simple
// indexes
$columns = array(
array( 'db' => '`security`.`settings_id`', 'dt' => 'settings_id' ),
array( 'db' => '`users`.`user_id`', 'dt' => 'user_id' ),
array( 'db' => '`users`.`username`', 'dt' => 'username' ),
array( 'db' => '`users`.`computer_name`', 'dt' => 'computer_name' ),
array( 'db' => '`security`.`disable_desktop`', 'dt' => 'disable_desktop' ),
array( 'db' => '`security`.`disable_start`', 'dt' => 'disable_start' ),
array( 'db' => '`security`.`disable_shutdown`', 'dt' => 'disable_shutdown' ),
array( 'db' => '`security`.`disable_run`', 'dt' => 'disable_run' ),
array( 'db' => '`security`.`disable_mouse`', 'dt' => 'disable_mouse' ),
array( 'db' => '`security`.`disable_bootkeys`', 'dt' => 'disable_bootkeys' ),
array( 'db' => '`security`.`disable_cp`', 'dt' => 'disable_cp' ),
array( 'db' => '`security`.`disable_network`', 'dt' => 'disable_network' ),
array( 'db' => '`security`.`disable_taskbar`', 'dt' => 'disable_taskbar' ),
array( 'db' => '`security`.`disable_clock`', 'dt' => 'disable_clock' ),
array( 'db' => '`security`.`disable_logoff`', 'dt' => 'disable_logoff' ),
array( 'db' => '`security`.`disable_startchange`', 'dt' => 'disable_startchange' ),
array( 'db' => '`security`.`disable_taskman`', 'dt' => 'disable_taskman' ),
array( 'db' => '`security`.`disable_clipboard`', 'dt' => 'disable_clipboard' ),
array( 'db' => '`security`.`disable_drives`', 'dt' => 'disable_drives' )
);
echo json_encode(
SSP::simple( $_GET, $db, $table, $primaryKey, $columns, $myJoin, "")
//SSP::simple( $_GET, $db, $table, $primaryKey, $columns, $myJoin, $myWhere)
);
ssp.class.php：
class SSP {
/**
* Create the data output array for the DataTables rows
*
* @param array $columns Column information array
* @param array $data Data from the SQL get
* @return array Formatted data in a row based format
*/
static function data_output ( $primaryKey, $columns, $data )
{
$out = array();
for ( $i=0, $ien=count($data) ; $i<$ien ; $i++ ) {
$row = array();
for ( $j=0, $jen=count($columns) ; $j<$jen ; $j++ ) {
$column = $columns[$j];
// Is there a formatter?
if ( isset( $column['formatter'] ) ) {
$row[ $column['dt'] ] = $column['formatter']( $data[$i][ $column['db'] ], $data[$i] );
}
else {
$row[ $column['dt'] ] = $data[$i][ $columns[$j]['db'] ];
}
}
$out[] = $row;
}
return $out;
}
/**
* Paging
*
* Construct the LIMIT clause for server-side processing SQL query
*
* @param array $request Data sent to server by DataTables
* @param array $columns Column information array
* @return string SQL limit clause
*/
static function limit ( $request, $columns )
{
$limit = '';
if ( isset($request['start']) && $request['length'] != -1 ) {
$limit = "LIMIT ".intval($request['start']).", ".intval($request['length']);
}
return $limit;
}
/**
* Ordering
*
* Construct the ORDER BY clause for server-side processing SQL query
*
* @param array $request Data sent to server by DataTables
* @param array $columns Column information array
* @return string SQL order by clause
*/
static function order ( $request, $columns )
{
$order = '';
if ( isset($request['order']) && count($request['order']) ) {
$orderBy = array();
$dtColumns = SSP::pluck( $columns, 'dt' );
for ( $i=0, $ien=count($request['order']) ; $i<$ien ; $i++ ) {
// Convert the column index into the column data property
$columnIdx = intval($request['order'][$i]['column']);
$requestColumn = $request['columns'][$columnIdx];
$columnIdx = array_search( $requestColumn['data'], $dtColumns );
$column = $columns[ $columnIdx ];
if ( $requestColumn['orderable'] == true ) {
$dir = $request['order'][$i]['dir'] === 'asc' ?
'ASC' :
'DESC';
$orderBy[] = ''.$column['db'].' '.$dir;
}
}
$order = 'ORDER BY '.implode(', ', $orderBy);
}
return $order;
}
/**
* Searching / Filtering
*
* Construct the WHERE clause for server-side processing SQL query.
*
* NOTE this does not match the built-in DataTables filtering which does it
* word by word on any field. It's possible to do here performance on large
* databases would be very poor
*
* @param array $request Data sent to server by DataTables
* @param array $columns Column information array
* @param array $bindings Array of values for PDO bindings, used in the
* sql_exec() function
* @return string SQL where clause
EDIT : added $mywhere functionality for passing initial filtering conditions
*/
static function filter ( $request, $columns, &$bindings, $myWhere )
{
$globalSearch = array();
$columnSearch = array();
$dtColumns = SSP::pluck( $columns, 'dt' );
if ( isset($request['search']) && $request['search']['value'] != '' ) {
$str = $request['search']['value'];
for ( $i=0, $ien=count($request['columns']) ; $i<$ien ; $i++ ) {
$requestColumn = $request['columns'][$i];
$columnIdx = array_search( $requestColumn['data'], $dtColumns );
$column = $columns[ $columnIdx ];
if ( $requestColumn['searchable'] == 'true' ) {
$binding = SSP::bind( $bindings, '%'.$str.'%', PDO::PARAM_STR );
$globalSearch[] = "".$column['db']." LIKE ".$binding;
}
}
}
// Individual column filtering
for ( $i=0, $ien=count($request['columns']) ; $i<$ien ; $i++ ) {
$requestColumn = $request['columns'][$i];
$columnIdx = array_search( $requestColumn['data'], $dtColumns );
$column = $columns[ $columnIdx ];
$str = $requestColumn['search']['value'];
if ( $requestColumn['searchable'] == 'true' &&
$str != '' ) {
$binding = SSP::bind( $bindings, '%'.$str.'%', PDO::PARAM_STR );
$columnSearch[] = "".$column['db']." LIKE ".$binding;
}
}
// Combine the filters into a single string
$where = '';
if ( count( $globalSearch ) ) {
$where = '('.implode(' OR ', $globalSearch).')';
}
if ( count( $columnSearch ) ) {
$where = $where === '' ?
implode(' AND ', $globalSearch) :
$where .' AND '. implode(' AND ', $globalSearch);
}
if ( $where !== '' ) {
$where = 'WHERE '.$where;
// add my clause
if ($myWhere !== '') {
$where .= ' AND '.$myWhere;
}
}
if ( $where == '' && $myWhere !== '') {
// add my clause
$where = 'WHERE '.$myWhere;
}
return $where;
}
/**
* Perform the SQL queries needed for an server-side processing requested,
* utilising the helper functions of this class, limit(), order() and
* filter() among others. The returned array is ready to be encoded as JSON
* in response to an SSP request, or can be modified if needed before
* sending back to the client.
*
* @param array $request Data sent to server by DataTables
* @param array $sql_details SQL connection details - see sql_connect()
* @param string $table SQL table to query
* @param string $primaryKey Primary key of the table
* @param array $columns Column information array
* @return array Server-side processing response array
*/
static function simple ( $request, $db, $table, $primaryKey, $columns, $myJoin, $myWhere )
{
$bindings = array();
//$db = SSP::sql_connect( $sql_details );
// Build the SQL query string from the request
$limit = SSP::limit( $request, $columns );
$order = SSP::order( $request, $columns );
$where = SSP::filter( $request, $columns, $bindings, $myWhere );
// Main query to actually get the data
$data = SSP::sql_exec( $db, $bindings,
"SELECT SQL_CALC_FOUND_ROWS ".implode(", ", SSP::pluck($columns, 'db'))."
FROM $table
$myJoin
$where
$order
$limit"
);
// Data set length after filtering
$resFilterLength = SSP::sql_exec( $db,
"SELECT FOUND_ROWS()"
);
$recordsFiltered = $resFilterLength[0][0];
//add my initial where clause for correct results
$dataWhere = ($myWhere !== '' ? 'WHERE '.$myWhere : '');
// Total data set length
$resTotalLength = SSP::sql_exec( $db,
"SELECT COUNT({$primaryKey})
FROM $table
$myJoin
$dataWhere"
);
$recordsTotal = $resTotalLength[0][0];
/*
* Output
*/
return array(
"draw" => intval( $request['draw'] ),
"recordsTotal" => intval( $recordsTotal ),
"recordsFiltered" => intval( $recordsFiltered ),
"data" => SSP::data_output( $primaryKey, $columns, $data )
);
}
/**
* Execute an SQL query on the database
*
* @param resource $db Database handler
* @param array $bindings Array of PDO binding values from bind() to be
* used for safely escaping strings. Note that this can be given as the
* SQL query string if no bindings are required.
* @param string $sql SQL query to execute.
* @return array Result from the query (all rows)
*/
static function sql_exec ( $db, $bindings, $sql=null )
{
// Argument shifting
if ( $sql === null ) {
$sql = $bindings;
}
$stmt = $db->prepare( $sql );
//echo $sql;
// Bind parameters
if ( is_array( $bindings ) ) {
for ( $i=0, $ien=count($bindings) ; $i<$ien ; $i++ ) {
$binding = $bindings[$i];
$stmt->bindValue( $binding['key'], $binding['val'], $binding['type'] );
}
}
// Execute
try {
$stmt->execute();
}
catch (PDOException $e) {
SSP::fatal( "An SQL error occurred: ".$e->getMessage() );
}
// Return all
return $stmt->fetchAll();
}
/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
* Internal methods
*/
/**
* Throw a fatal error.
*
* This writes out an error message in a JSON string which DataTables will
* see and show to the user in the browser.
*
* @param string $msg Message to send to the client
*/
static function fatal ( $msg )
{
echo json_encode( array(
"error" => $msg
) );
exit(0);
}
/**
* Create a PDO binding key which can be used for escaping variables safely
* when executing a query with sql_exec()
*
* @param array &$a Array of bindings
* @param * $val Value to bind
* @param int $type PDO field type
* @return string Bound key to be used in the SQL where this parameter
* would be used.
*/
static function bind ( &$a, $val, $type )
{
$key = ':binding_'.count( $a );
$a[] = array(
'key' => $key,
'val' => $val,
'type' => $type
);
return $key;
}
/**
* Pull a particular property from each assoc. array in a numeric array,
* returning and array of the property values from each item.
*
* @param array $a Array to get data from
* @param string $prop Property to read
* @return array Array of property values
*/
static function pluck ( $a, $prop )
{
$out = array();
for ( $i=0, $len=count($a) ; $i<$len ; $i++ ) {
$out[] = $a[$i][$prop];
}
return $out;
}
}
编辑：
这是SSP::data_output( $primaryKey, $columns, $data ) 的结果。我不得不将其打印到文件中，因为我无法在屏幕上打印/显示。结果很明显，代码的数据部分出现了问题，因为它没有返回任何内容，但是，它返回了正确数量的结果（在本例中为 5）。请注意，命名是不同的，因为这些是返回给 DataTables 的名称，而不是实际的 db 列名，但是，这可能与它有关。
Array
(
[0] => Array
(
[settings_id] =>
[user_id] =>
[username] =>
[computer_name] =>
[disable_desktop] =>
[disable_start] =>
[disable_shutdown] =>
[disable_run] =>
[disable_mouse] =>
[disable_bootkeys] =>
[disable_cp] =>
[disable_network] =>
[disable_taskbar] =>
[disable_clock] =>
[disable_logoff] =>
[disable_startchange] =>
[disable_taskman] =>
[disable_clipboard] =>
[disable_drives] =>
[DT_RowId] =>
)
[1] => Array
(
[settings_id] =>
[user_id] =>
[username] =>
[computer_name] =>
[disable_desktop] =>
[disable_start] =>
[disable_shutdown] =>
[disable_run] =>
[disable_mouse] =>
[disable_bootkeys] =>
[disable_cp] =>
[disable_network] =>
[disable_taskbar] =>
[disable_clock] =>
[disable_logoff] =>
[disable_startchange] =>
[disable_taskman] =>
[disable_clipboard] =>
[disable_drives] =>
[DT_RowId] =>
)
[2] => Array
(
[settings_id] =>
[user_id] =>
[username] =>
[computer_name] =>
[disable_desktop] =>
[disable_start] =>
[disable_shutdown] =>
[disable_run] =>
[disable_mouse] =>
[disable_bootkeys] =>
[disable_cp] =>
[disable_network] =>
[disable_taskbar] =>
[disable_clock] =>
[disable_logoff] =>
[disable_startchange] =>
[disable_taskman] =>
[disable_clipboard] =>
[disable_drives] =>
[DT_RowId] =>
)
[3] => Array
(
[settings_id] =>
[user_id] =>
[username] =>
[computer_name] =>
[disable_desktop] =>
[disable_start] =>
[disable_shutdown] =>
[disable_run] =>
[disable_mouse] =>
[disable_bootkeys] =>
[disable_cp] =>
[disable_network] =>
[disable_taskbar] =>
[disable_clock] =>
[disable_logoff] =>
[disable_startchange] =>
[disable_taskman] =>
[disable_clipboard] =>
[disable_drives] =>
[DT_RowId] =>
)
[4] => Array
(
[settings_id] =>
[user_id] =>
[username] =>
[computer_name] =>
[disable_desktop] =>
[disable_start] =>
[disable_shutdown] =>
[disable_run] =>
[disable_mouse] =>
[disable_bootkeys] =>
[disable_cp] =>
[disable_network] =>
[disable_taskbar] =>
[disable_clock] =>
[disable_logoff] =>
[disable_startchange] =>
[disable_taskman] =>
[disable_clipboard] =>
[disable_drives] =>
[DT_RowId] =>
)
)
更多信息 - 在下面显示的代码的此时查看 $data 会返回所有正确的值。
$data = SSP::sql_exec( $db, $bindings,
"SELECT SQL_CALC_FOUND_ROWS ".implode(", ", SSP::pluck($columns, 'db'))."
FROM $table
$myJoin
$where
$order
$limit"
);
这是返回数组的一部分（一行），上面有正确的值：
[3] => Array
(
[settings_id] => 1
[0] => 1
[user_id] => 11
[1] => 11
[username] => steve
[2] => steve
[computer_name] => TESTING
[3] => TESTING
[disable_desktop] => 1
[4] => 1
[disable_start] => 0
[5] => 0
[disable_shutdown] => 0
[6] => 0
[disable_run] => 0
[7] => 0
[disable_mouse] => 0
[8] => 0
[disable_bootkeys] => 0
[9] => 0
[disable_cp] => 0
[10] => 0
[disable_network] => 0
[11] => 0
[disable_taskbar] => 0
[12] => 0
[disable_clock] => 0
[13] => 0
[disable_logoff] => 0
[14] => 0
[disable_startchange] => 0
[15] => 0
[disable_taskman] => 0
[16] => 0
[disable_clipboard] => 0
[17] => 0
[disable_drives] => 0
[18] => 0
)
不完全确定这是否是正确的输出，但是，我相信您可以通过名称或索引引用数据表中的数据来解释此输出。
编辑：
我进一步缩小了问题的范围。静态函数 data_output ( $primaryKey, $columns, $data ) 是预期的问题的一部分。 $primaryKey 和 $columns 具有正确的值，但是 $data 没有。
在函数中，当您到达实际设置值的部分时，数组中没有要设置的值。
$row[ $column['dt'] ] = $data[$i][ $columns[$j]['db'] ];
这里$row[ $column['dt'] ] 是正确的，但是$data[$i][ $columns[$j]['db'] ]; 没有db 值。正如您在上面 $data 的示例输出中看到的那样，不存在 db 值，而是将 dt 值与索引一起作为相同的值。通过将其更改为 dt 我的表显示数据，但是，这会破坏其他一些东西。我不确定为什么 $data 没有包含应有的 db 值。
【问题讨论】：
-
尝试转储整个查询并尝试将它们直接执行到mysql命令行，看看是否有任何错误。
-
如果我理解正确，那将无济于事。我可以很容易地用我想要的查询数据库......这是一个修改这个脚本以接受我所追求的表连接的问题。 draw、recordsTotal 和 recordsFiltered 正在正确返回。
"data" => SSP::data_output( $primaryKey, $columns, $data )似乎是所有列都返回 null 的问题。 -
你能在 SSP::sql_exec(, 之后尝试转储 $data 变量吗？
标签： php sql pdo jquery-datatables