Question

我有一个HTML搜索，它通过$ _GET将变量传递给PHP，PHP使用这些传递的变量来构建查询字符串。我面临的问题是构建一个查询字符串，该字符串可能只包含一个搜索条件，或者可能包含多个搜索条件。如果只有一个标准用于搜索，则查询中不需要“AND”语句。如果使用多个标准，则每个标准之间将需要“AND”。如何处理这个“与”相关的问题？

    <?php

    $IKfield01 = (isset($_GET['field01']) ? $_GET['field01'] : null);
    $IKfield02 = (isset($_GET['field02']) ? $_GET['field02'] : null);
    $IKfield03 = (isset($_GET['field03']) ? $_GET['field03'] : null);
    $IKfield04 = (isset($_GET['field04']) ? $_GET['field04'] : null);
    $IKfield05 = (isset($_GET['field05']) ? $_GET['field05'] : null);
    $IKfield06 = (isset($_GET['field06']) ? $_GET['field06'] : null);
    $IKfield07 = (isset($_GET['field07']) ? $_GET['field07'] : null);
    $IKfield08 = (isset($_GET['field08']) ? $_GET['field08'] : null);
    $IKfield09 = (isset($_GET['field09']) ? $_GET['field09'] : null);
    $IKfield10 = (isset($_GET['field10']) ? $_GET['field10'] : null);

    $searchfield01 = mysqli_real_escape_string($mysqli,$IKfield01);
    $searchfield02 = mysqli_real_escape_string($mysqli,$IKfield02);
    $searchfield03 = mysqli_real_escape_string($mysqli,$IKfield03);
    $searchfield04 = mysqli_real_escape_string($mysqli,$IKfield04);
    $searchfield05 = mysqli_real_escape_string($mysqli,$IKfield05);
    $searchfield06 = mysqli_real_escape_string($mysqli,$IKfield06);
    $searchfield07 = mysqli_real_escape_string($mysqli,$IKfield07);
    $searchfield08 = mysqli_real_escape_string($mysqli,$IKfield08);
    $searchfield09 = mysqli_real_escape_string($mysqli,$IKfield09);
    $searchfield10 = mysqli_real_escape_string($mysqli,$IKfield10);

    $prequery = "SELECT * FROM table WHERE";
    $prequery1 = "";
    $prequery2 = "";
    $prequery3 = "";
    $prequery4 = "";
    $prequery5 = "";
    $prequery6 = "";
    $prequery7 = "";
    $prequery8 = "";
    $prequery9 = "";
    $prequery10 = "";
    $prequery11 = "";
    $prequery12 = " LIMIT $maxsearch";

    if ($searchfield01 != '') $prequery2 = "genus LIKE '%$searchfield01%'";
    if ($searchfield02 != '') $prequery3 = "AND specificEpithet LIKE '%$searchfield02%'";
    if ($searchfield03 != '') $prequery4 = "AND stateProvince LIKE '%$searchfield03%'";
    if ($searchfield04 != '') $prequery5 = "AND county LIKE '%$searchfield04%'";
    if ($searchfield05 != '') $prequery6= "AND family LIKE '%$searchfield05%'";
    if ($searchfield06 != '') $prequery7 = "AND locality LIKE '%$searchfield06%'";
    if ($searchfield07 != '') $prequery8 = "AND OtherCatalogNumbers LIKE '%$searchfield07%'";
    if ($searchfield08 != '') $prequery9 = "AND recordedBy LIKE '%$searchfield08%'";
    if ($searchfield09 != '') $prequery10 = "AND recordNumber LIKE '$searchfield09'";
    if ($searchfield10 != '') $prequery11 = "AND catalogNumber LIKE '%$searchfield10%'";

    $query = "$prequery $prequery2 $prequery3 $prequery4 $prequery5 $prequery6 $prequery7 $prequery8 $prequery9 $prequery10 $prequery11 $prequery12";

    $row_count = 0;
    $result = mysql_query($query) or die("MS-Query Error in select-query");
    $querystats=mysql_num_rows($result); 
    $resultcounter=1;

    while ($row = mysql_fetch_array($result))
    {
    $IKdfield01 = "$row[field01]";
    $IKdfield02 = "$row[field02]";
    $IKdfield03 = "$row[field03]";
    $IKdfield04 = "$row[field04]";
    $IKdfield05 = "$row[field05]";
    $IKdfield06 = "$row[field06]";
    $IKdfield07 = "$row[field07]";
    $IKdfield08 = "$row[field08]";
    $IKdfield09 = "$row[field09]";
    $IKdfield10 = "$row[field10]";
    $IKdfield11 = "$row[field11]";
    $IKdfield12 = "$row[field12]";
    $IKdfield13 = "$row[field13]";
    $IKdfield14 = "$row[field14]";
    $IKdfield15 = "$row[field15]";
    $IKdfield16 = "$row[field16]";
    $IKdfield17 = "$row[field17]";
    $IKdfield18 = "$row[field18]";
    $IKdfield19 = "$row[field19]";
    $IKdfield20 = "$row[field20]";
    $IKdfield21 = "$row[field21]";
    $IKdfield22 = "$row[field22]";
    $IKdfield23 = "$row[field23]";
    $IKdfield24 = "$row[field24]";
    $IKdfield25 = "$row[field25]";
    $IKdfield26 = "$row[field26]";
    $IKdfield27 = "$row[field27]";

    //output results

    echo "$IKfield01, $IKfield02, $IKfield03, $IKfield04, $IKfield05, $IKfield06, $IKfield07, $IKfield08, $IKfield09, $IKfield10, $IKfield11, $IKfield12";
    echo "$IKfield13, $IKfield14, $IKfield15, $IKfield16, $IKfield17, $IKfield18, $IKfield19, $IKfield20, $IKfield21, $IKfield22, $IKfield23, $IKfield24";
    echo "$IKfield25, $IKfield26, $IKfield27, (EOR) <br>";

    $resultcounter++;
    $row_count++;
    }

    ?>

Answer 1

You could use WHERE 1以便您始终以AND结束每个条款。

另一个解决方案是使用条件创建变量$where并在添加子句之前检查是否有任何内容，如果是，则添加AND

<?php
$sql = "SELECT * FROM table"
$where = "";
// ...

if($myparam) {
    if(strlen($where) > 0) $where .= ' AND';
    $where .= " myparam ='myval'";
}
// ...
if(strlen($where) > 0) $sql = $sql . ' WHERE ' . $where;

Answer 2

我会构建一个参数数组，并将它们内嵌到查询中：

$query_array = array();
$fields = array(
    1=>'genus', 
    2=>'specificEpithet', 
    3=>'stateProvince', 
    4=>'county',
    5=>'family',
    6=>'locality',
    7=>'OtherCatalogNumbers',
    8=>'recordedBy',
    9=>'recordNumber',
    10=>'catalogNumber'
    );
for($i = 1; $i <= 10; $i++){
    $field = 'field' . str_pad($i, 2, " ", STR_PAD_LEFT);
    if(!isset($_GET[$field])
        continue;

    $value = mysqli_real_escape_string($mysqli,$_GET[$field]);
    $query_array[] = $fields[$i] . ' LIKE %' . $value . '%';
}

$query = "SELECT * FROM table WHERE " . implode(' AND ', $query_array) . " LIMIT $maxsearch";
$row_count = 0;
$result = mysql_query($query) or die("MS-Query Error in select-query");

//etc

从Passed变量构建MySQL查询字符串

2 个答案: