我是Php的新手，我正试图将参数传递给从我维护的表中获得的SQL语句。传递的参数可以是product_id、日期，或者在本例中为设置限制。这是我目前为止得到的。。。需要建议来解决这个问题。。
存储在表中的DB语句web_query:
SELECT * FROM adhoc_signal.`table 2` limit :startnum , :endnum
PHP脚本：
<?php
$con = mysqli_connect("localhost", "my_user", "my_password", "world");
/* check connection */
if (!$con) {
printf("Connect failed: %s'n", mysqli_connect_error());
exit();
}
//Initialize variables
$per_page=8;
if (isset($_GET[“page”])) {
$page = $_GET[“page”];
}
else {
$page=1;
}
// Page will start from 0 and Multiple by Per Page
$start_from = ($page-1) * $per_page;
$query = mysqli_query($con,"SELECT qry_text from web_query where report_id = 1") or die("Error : Failed to fetch Query records: " . mysql_error());
if (!$query) {
$error = 'Error fetching reports: ' . mysqli_error($con);
exit();
}
// echo 'I got some webqry records';
while ($rows = mysqli_fetch_array($query)) {
if (!empty($rows) || (array() !== $rows)) {
// Following Problematic prepare statement...
if ($stmt = mysqli_prepare($con, $rows['qry_text'])) {
mysqli_stmt_bind_param($stmt,'sssd', $start_page, $per_page);
$pagres = mysqli_query($con, $stmt);
$pagnum = mysqli_num_rows($pagres);
$pagnumcol= $pagres->field_count;
print "Value of stmt : $stmt magnum : $pagnum";
}
else {
print "Prepare statement is returning : False";
}
}
或者，如果我将DB SQL语句更改为：select*from adhoc_signal。table 2和在不准备Php脚本的情况下修改Php脚本，它们似乎工作得很好。
<?php
$con = mysqli_connect("localhost", "my_user", "my_password", "world");
/* check connection */
if (!$con) {
printf("Connect failed: %s'n", mysqli_connect_error());
exit();
}
//Initialize variables
$per_page=8;
if (isset($_GET[“page”])) {
$page = $_GET[“page”];
}
else {
$page=1;
}
// Page will start from 0 and Multiple by Per Page
$start_from = ($page-1) * $per_page;
$query = mysqli_query($con,"SELECT qry_text from web_query where report_id = 1") or die("Error : Failed to fetch Query records: " . mysql_error());
if (!$query) {
$error = 'Error fetching reports: ' . mysqli_error($con);
exit();
}
// echo 'I got some webqry records';
while ($rows = mysqli_fetch_array($query)) {
if (!empty($rows) || (array() !== $rows)) {
$result = mysqli_query($con, $rows['qry_text']) or die("Error : Why is the Query failing : ". mysql_error());
$num=mysqli_num_rows($result);
$numcol= $result->field_count;
if ($num > 0) {
print '<div class="panel panel-primary"> ';
print '<div class="panel-heading"> ';
print '<h3 class="panel-title">Results</h3> ';
print '</div>';
print '<div id="gentable" class="table-responsive"> ';
print '<table class="table-responsive table-bordered table-condensed table-hover" > ';
print '<th><td><strong>Preferred Term</strong></td></th>';
while ($row = mysqli_fetch_array($result) ) {
print " <tr> 'n";
foreach ($row as $field ){
print " <td>$field</td> 'n";
} // end foreach
print '</tr>';
} // end of while
print "</table>";
print "</div>"; // End of panel body
print "</div>";
} // end of if
}
绑定参数后，您需要执行准备好的语句，而不是执行$pagres = mysqli_query($con, $stmt);
此外，您不能混合使用过程调用方法和OO调用方法。
if ($stmt = mysqli_prepare($con, $rows['qry_text'])) {
mysqli_stmt_bind_param($stmt,'sssd', $start_page, $per_page);
//mysqli_query($con, $stmt);
mysqli_stmt_execute($stmt);
$pagnum = mysqli_stmt_num_rows($stmt);
$pagnumcol= mysqli_stmt_field_count($stmt);
}
此外，我认为你不想在这行中打印$stmt
print "Value of stmt : $stmt magnum : $pagnum";