我使用datatable jQuery插件从MySQL数据库渲染多个连接表。我能够根据需要渲染表格。但搜索功能无效。
观察：
当我尝试使用“WHERE”子句在我的dbms中运行查询时，我发现“WHERE”子句只有在“GROUP BY”语句之前才会运行。所以在我的代码中它也必须在“GROUP BY”语句之前，而$ sql在“GROUP BY”语句之后连接“WHERE”子句。我不知道如何在运行时在“GROUP BY”语句之前插入WHERE子句（带有搜索值）。
我提供了两个文件的代码，（1） Index.php （带有表的文件和将响应请求发送到response.php文件的js）。 （2） response.php （包含sql和搜索代码的文件，它将json编码数据发送到index.php）。我使用的是数据表版本1.10.10。我正在关注此tutorial
以下是我的代码：
的index.php
<head>
...
<link href="css/bootstrap.css" rel="stylesheet" type="text/css">
<link href="css/customize.css" rel="stylesheet" type="text/css" media="screen">
<link rel="stylesheet" type="text/css" href="css/font-awesome.css">
<link rel="stylesheet" type="text/css" href="css/dataTables.bootstrap.css">
<link rel="stylesheet" type="text/css" href="css/jquery.dataTables.css">
...
</head>
<body>
...
<div class="row">
<div id="" class="col-lg-12 col-md-12 col-sm-12 col-xs-12">
<table id="employee_grid" class="display table-bordered">
<thead>
<tr>
<th class="col-lg-2 col-md-2 col-sm-2 col-xs-2">Student Name</th>
<th class="col-lg-1 col-md-1 col-sm-1 col-xs-1">Gender</th>
<th class="col-lg-1 col-md-1 col-sm-1 col-xs-1">City</th>
<th class="col-lg-3 col-md-3 col-sm-3 col-xs-3">Course Description</th>
<th class="col-lg-2 col-md-2 col-sm-2 col-xs-2">Subject</th>
<th class="col-lg-1 col-md-1 col-sm-1 col-xs-1 text-right">Scholarship</th>
<th class="col-lg-2 col-md-2 col-sm-2 col-xs-2">View Details</th>
</tr>
</thead>
</table>
</div>
</div>
...
<script>
$( document ).ready(function() {
$('#employee_grid').DataTable({
"bProcessing": true,
"serverSide": true,
"autoWidth": true,
"stateSave": true,
"lengthMenu": [ 10, 25, 50, 100 ],
"ajax":{
url :"response_b.php", // json datasource
type: "post", // type of method,GET/POST/DELETE
error: function(){
$("#employee_grid_processing").css("display","none");
}
},
"columnDefs": [ {
"targets": 6,
"data": "StudentID",
"render": function ( data, type, full, meta ) {
return '<a href="beneficiary.php?StudentID="'+data+'">'+data+'</a>';
}
}]
});
});
</script>
</body>
response.php
<?php
//include connection file
include_once("connection.php");
// initilize all variable
$params = $columns = $totalRecords = $data = array();
$params = $_REQUEST;
//define index of column
$columns = array(
0 => '`Full Name`',
1 => 'Gender',
2 => 'CityName',
3 => 'CourseDescriptionLong',
4 => '`Subject`',
5 => 'ScholarshipAwarded',
6 => 'StudentID'
);
$where = $sqlTot = $sqlRec = "";
// check search value exist
if( !empty($params['search']['value']) ) {
$where .=" WHERE ";
$where .=" (`Full Name` LIKE '".$params['search']['value']."%' ";
$where .=" OR CityName LIKE '".$params['search']['value']."%' ";
$where .=" OR CourseDescriptionLong LIKE '".$params['search']['value']."%' )";
}
// getting total number records without any search
$sql = "
SELECT fullnames.`full name`,
studentdetails.gender,
lt_cities.cityname,
lt_coursedescription.coursedescriptionlong,
lt_coursesubject.`subject`,
Sum(scholarshipdetails.scholarshipawarded),
studentdetails.studentid,
coursedetails.coursetype,
lt_coursedescription.coursedescriptionshort,
scholarshipdetails.scholarshipyear
FROM studentdetails
INNER JOIN scholarshipdetails
ON studentdetails.studentid = scholarshipdetails.studentid
INNER JOIN coursedetails
ON studentdetails.studentid = coursedetails.studentid
AND scholarshipdetails.scholarshipyear =
coursedetails.scholarshipyear
LEFT JOIN lt_coursedescription
ON coursedetails.courseid = lt_coursedescription.courseid
INNER JOIN tuitionfeedetails
ON studentdetails.studentid = tuitionfeedetails.studentid
AND scholarshipdetails.scholarshipyear =
tuitionfeedetails.scholarshipyear
INNER JOIN fullnames
ON studentdetails.studentid = fullnames.studentid
INNER JOIN lt_cities
ON lt_cities.cityid = studentdetails.city
LEFT JOIN lt_coursesubject
ON lt_coursesubject.courseid = lt_coursedescription.courseid
AND lt_coursesubject.subjectid = coursedetails.coursesubject
GROUP BY studentdetails.studentid";
$sqlTot .= $sql;
$sqlRec .= $sql;
//concatenate search sql if value exist
if(isset($where) && $where != '') {
$sqlTot .= $where;
$sqlRec .= $where;
}
$sqlRec .= " ORDER BY ". $columns[$params['order'][0]['column']]." ".$params['order'][0]['dir']." LIMIT ".$params['start']." ,".$params['length']." ";
$queryTot = mysqli_query($conn, $sqlTot) or die("database error:". mysqli_error($conn));
$totalRecords = mysqli_num_rows($queryTot);
$queryRecords = mysqli_query($conn, $sqlRec) or die("error to fetch employees data");
//iterate on results row and create new index array of data
while( $row = mysqli_fetch_row($queryRecords) ) {
$data[] = $row;
}
$json_data = array(
"draw" => intval( $params['draw'] ),
"recordsTotal" => intval( $totalRecords ),
"recordsFiltered" => intval($totalRecords),
"data" => $data // total data array
);
echo json_encode($json_data); // send data as json format
?>
我已经在Stack Overflow上研究了这类问题，并且答案中有很多问题，但它们似乎都不适合我。
任何人都可以指导我吗？
答案 0 :(得分：0)
我已在 WHERE 条件之后更新 GROUP BY 查询的代码。
<?php
//include connection file
include_once("connection.php");
// initilize all variable
$params = $columns = $totalRecords = $data = array();
$params = $_REQUEST;
//define index of column
$columns = array(
0 => '`Full Name`',
1 => 'Gender',
2 => 'CityName',
3 => 'CourseDescriptionLong',
4 => '`Subject`',
5 => 'ScholarshipAwarded',
6 => 'StudentID'
);
$where = $sqlTot = $sqlRec = "";
// check search value exist
if( !empty($params['search']['value']) ) {
$where .=" WHERE ";
$where .=" (`Full Name` LIKE '".$params['search']['value']."%' ";
$where .=" OR CityName LIKE '".$params['search']['value']."%' ";
$where .=" OR CourseDescriptionLong LIKE '".$params['search']['value']."%' )";
}
// getting total number records without any search
$sql = "SELECT fullnames.`Full Name`, studentdetails.Gender, lt_cities.CityName, lt_coursedescription.CourseDescriptionLong, lt_coursesubject.`Subject`, Sum(scholarshipdetails.ScholarshipAwarded), studentdetails.StudentID, coursedetails.CourseType, lt_coursedescription.CourseDescriptionShort, scholarshipdetails.ScholarshipYear FROM studentdetails INNER JOIN scholarshipdetails ON studentdetails.StudentID = scholarshipdetails.StudentID INNER JOIN coursedetails ON studentdetails.StudentID = coursedetails.StudentID AND scholarshipdetails.ScholarshipYear = coursedetails.Scholarshipyear LEFT JOIN lt_coursedescription ON coursedetails.CourseID = lt_coursedescription.CourseID INNER JOIN tuitionfeedetails ON studentdetails.StudentID = tuitionfeedetails.StudentID AND scholarshipdetails.ScholarshipYear = tuitionfeedetails.ScholarshipYear INNER JOIN fullnames ON studentdetails.StudentID = fullnames.StudentID INNER JOIN lt_cities ON lt_cities.CityID = studentdetails.City LEFT JOIN lt_coursesubject ON lt_coursesubject.CourseID = lt_coursedescription.CourseID AND lt_coursesubject.SubjectID = coursedetails.CourseSubject ";
$sqlTot .= $sql;
$sqlRec .= $sql;
//concatenate search sql if value exist
if(isset($where) && $where != '') {
$sqlTot .= $where;
$sqlRec .= $where;
}
$sqlRec .= " GROUP BY studentdetails.StudentID ";
$sqlRec .= " ORDER BY ". $columns[$params['order'][0]['column']]." ".$params['order'][0]['dir']." LIMIT ".$params['start']." ,".$params['length']." ";
$queryTot = mysqli_query($conn, $sqlTot) or die("database error:". mysqli_error($conn));
$totalRecords = mysqli_num_rows($queryTot);
$queryRecords = mysqli_query($conn, $sqlRec) or die("error to fetch employees data");
//iterate on results row and create new index array of data
while( $row = mysqli_fetch_row($queryRecords) ) {
$data[] = $row;
}
$json_data = array(
"draw" => intval( $params['draw'] ),
"recordsTotal" => intval( $totalRecords ),
"recordsFiltered" => intval($totalRecords),
"data" => $data // total data array
);
echo json_encode($json_data); // send data as json format
?>