优化PHP SQL查询的最佳方法

问：

我正在寻找有关优化代码的最佳方法的指针。该查询旨在拉取我在 wordpress 站点中建立连接的单独 sql Server 表中的供应商数据库。

我根据在搜索字段中传递的值创建了三个不同的查询。它要么是供应商名称、类别名称，要么是最终的类别 ID。我正在尝试优化，因此将来当我需要更新正在拉取的列时，我不必更新多个语句。

任何想法或指导将不胜感激。

<?php
$searchInput='xyz';
if(isset($_GET['searchInput'])){
    $searchInput= $_GET['searchInput'];
 }
 $searchcat_id ='';
 if(isset($_GET['category_id'])){
    $searchcat_id= $_GET['category_id'];
 }
if (isset($_POST['searchInput'])) {
    $searchInput = sanitize_text_field($_POST['searchInput']);
}
$conn = get_sql_connect();
if ($conn === false) {
    $content = ['Error in connecting the SQL Server'];
} else {
    if($searchInput=='All Vendors'){
        $query = "select * from vendor";
    }else{
        $query = "select * from vendor where vendorName LIKE '".$searchInput."'";
    }
    $datatable_value = array();
    $stm = sqlsrv_query($conn, $query);
    $flag = 0;
    // When there is no categry name in search. We are only searching by Vendor name
    while ($rows = sqlsrv_fetch_array($stm, SQLSRV_FETCH_ASSOC)) {
        $flag = 1;
        $ven_query = "SELECT cat.category_name, ven.vendorID
                    FROM vendor AS ven
                    JOIN vendor_category AS vencat ON ven.vendorID = vencat.vendor_id 
                    JOIN category AS cat ON vencat.category_id  = cat.category_id 
                    WHERE ven.vendorName LIKE '%".str_replace("'","''",$rows['vendorName'])."%'";
        $ven_stm = sqlsrv_query($conn, $ven_query);
        while ($values = sqlsrv_fetch_array($ven_stm, SQLSRV_FETCH_ASSOC)) {
            $rows['serviceCategory'] = $values['category_name'];
            $rows['Details'] = '<a href="'.get_home_url().'/vendor-information/?vendor='.$searchInput.'&category='.$values['category_name'].'&id='.$values['vendorID'].'">View</a>';
            $datatable_value[] = $rows;
        }
    }
    // We are seaching by category name and no Vendor.
    if($flag == 0 && $searchcat_id == ''){
        $cat_query = "SELECT
                        V.vendorID,
                        V.vendorName,
                        V.contact_name,
                        V.email,
                        V.phone,
                        V.supplierID,
                        C.category_name
                    FROM
                        vendor AS V
                    JOIN
                        vendor_category AS VC ON V.vendorID = VC.vendor_id
                    JOIN
                        category AS C ON VC.category_id = C.category_id
                    WHERE
                        C.category_name LIKE '%".str_replace("'","''",$searchInput)."%'";
        $cat_stm = sqlsrv_query($conn, $cat_query);
        if(!empty($cat_stm)){
            while ($value = sqlsrv_fetch_array($cat_stm, SQLSRV_FETCH_ASSOC)) {
                $value['Details'] = '<a href="'.get_home_url().'/vendor-information/?vendor='.$value['vendorName'].'&category='.$searchInput.'&id='.$value['vendorID'].'">View</a>';
                $datatable_value[] = $value;
            }
        }
    }else{
        $temp_query = "SELECT DISTINCT c4.category_id
                        FROM category c1
                        JOIN category c2 ON c1.category_id = c2.category_id OR c1.category_id = c2.parent_category_id
                        JOIN category c3 ON c2.category_id = c3.category_id OR c2.category_id = c3.parent_category_id
                        JOIN category c4 ON c3.category_id = c4.category_id OR c3.category_id = c4.parent_category_id
                        WHERE c1.category_id = ".$searchcat_id;
        $temp_stm = sqlsrv_query($conn, $temp_query);
        if(!empty($temp_stm)){
            while ($value_temp = sqlsrv_fetch_array($temp_stm, SQLSRV_FETCH_ASSOC)) {
                //echo $value_temp['category_id'].'----';                
                $cat_query = "SELECT
                                V.vendorID,
                                V.vendorName,
                                V.contact_name,
                                V.email,
                                V.phone,
                                V.supplierID,
                                C.category_name
                            FROM
                                vendor AS V
                            JOIN
                                vendor_category AS VC ON V.vendorID = VC.vendor_id
                            JOIN
                                category AS C ON VC.category_id = C.category_id
                            WHERE
                                C.category_id = ".$value_temp['category_id'];
                //echo $cat_query.'/n'; 
                $cat_stm = sqlsrv_query($conn, $cat_query);
                if(!empty($cat_stm)){
                    //echo 'here::::';
                    while ($value = sqlsrv_fetch_array($cat_stm, SQLSRV_FETCH_ASSOC)) {
                        //print_r($value);
                        $value['Details'] = '<a href="'.get_home_url().'/vendor-information/?vendor='.$value['vendorName'].'&category='.$searchInput.'&id='.$value['vendorID'].'">View</a>';
                        $datatable_value[] = $value;
                    }
                }
            }
        }
    }
}
?>