JavaScript搜索数据库

我正在做一个搜索查询，搜索一个非常小的数据库。我终于让代码运行，没有错误，但我无法看到任何结果。我只是好奇我做错了什么。任何帮助都将不胜感激

// Create privatized scope using a self-executing function
(function() {

// Variable initialization (DO NOT FIX ANY OF THE BELOW VAR's)
var resultsDIV = document.getElementById("results"),
    searchInput = document.forms[0].search,
    currentSearch = ''
    ;


// Validates search query
var validate = function(query) {

    // Trim whitespace from start and end of search query
    while(query.charAt(0) ===" ") {
        query = query.substring(1, query.length);
    };
    while(query.charAt(query.length-1) === " ") {
        query = query.substring(0, query.length-1);
    };

    // Check search length, must have 3 characters
    if(query.length < 3){
        alert("Your search query is too small, try again.");

        // (DO NOT FIX THE LINE DIRECTLY BELOW)
        searchInput.focus();
        return;
    };

    search(query);
};

// Finds search matches
var search = function(query) {

    // split the user's search query string into an array
    var queryArray = query.join(" ");

    // array to store matched results from database.js
    var results = [];

    // loop through each index of db array
    for(var i=0, j=db.length; i<j; i++){

        // each db[i] is a single video item, each title ends with a pipe "|"
        // save a lowercase variable of the video title
        var dbTitleEnd = db[i].indexOf('|');
        var dbitem = db[i].tolowercase().substring(0, dbTitleEnd);
    };
        // loop through the user's search query words
        // save a lowercase variable of the search keyword
        for(var ii=0, jj=queryArray.length; ii<jj; ii++){
            var qitem = queryArray[ii].tolowercase();

            // is the keyword anywhere in the video title?
            // If a match is found, push full db[i] into results array
            var compare = dbitem.indexOf(qitem);
            if(compare !== -1){
                results.push(db[i]);
            };



    results.sort();

    // Check that matches were found, and run output functions
    if(results.length === 0) {
        noMatch();
    } else{
        showMatches(results);
    };
};

// Put "No Results" message into page (DO NOT FIX THE HTML VAR NOR THE innerHTML)
var noMatch = function(){
    var html = ''+
        '<p>No Results found.</p>'+
        '<p style="font-size:10px;">Try searching for "JavaScript".  Just an idea.</p>'
    ;
    resultsDIV.innerHTML = html;
};

// Put matches into page as paragraphs with anchors
var showMatches = function(results){

    // THE NEXT 4 LINES ARE CORRECT.
    var html = '<p>Results</p>', 
        title, 
        url
    ;

    // loop through all the results search() function
    for(var i=0, j=results.length; i<j; i++){

        // title of video ends with pipe
        // pull the title's string using index numbers
        titleEnd = results[i].indexOf('|');
        title = results[i].subString(0, titleEnd);

        // pull the video url after the title
        url = results[i].substring(results[i].indexOf('|')+1, results[i].length);

        // make the video link - THE NEXT LINE IS CORRECT.
        html += '<p><a href=' + url + '>' + title + '</a></p>';
    };
    resultsDIV.innerHTML = html; //THIS LINE IS CORRECT.
};

// The onsubmit event will be reviewed in upcoming Course Material.
// THE LINE DIRECTLY BELOW IS CORRECT
document.forms[0].onsubmit = function(){
    var query = searchInput.value;
    validate(query);

    // return false is needed for most events - this will be reviewed in upcoming course material
    // THE LINE DIRECTLY BELOW IS CORRECT
    return false;
};

})();

//使用自执行函数创建私有化作用域
（功能（）{
//变量初始化（不要修复以下任何变量）
var resultsDIV=document.getElementById（“结果”），
searchInput=文档。表单[0]。搜索，
currentSearch=“”
;
//验证搜索查询
var validate=函数（查询）{
//从搜索查询的开始和结束修剪空白
while（query.charAt（0）==“”）{
query=query.substring（1，query.length）；
};
while（query.charAt（query.length-1）==“”）{
query=query.substring（0，query.length-1）；
};
//检查搜索长度，必须有3个字符
if（query.length<3）{
警报（“您的搜索查询太小，请重试。”）；
//（不要直接在下方固定管线）
searchInput.focus（）；
返回；
};
搜索（查询）；
};
//查找搜索匹配项
变量搜索=函数（查询）{
//将用户的搜索查询字符串拆分为数组
var queryArray=query.join（“”）；
//用于存储database.js中匹配结果的数组
var结果=[]；
//循环遍历db数组的每个索引
对于（var i=0，j=db.length；i虽然我可能没有您那么先进，但使用PHP进行MySQL搜索并通过Ajax返回结果可能会更简单。互联网上有很多示例和教程，所以它可能会有所帮助

成功！
有此注释：
//将…拆分为一个数组
，然后执行：
var queryArray=query.join（“”；
？？看起来您需要拆分（“”）

这里。

//下面这行是正确的

肯定是我遇到过的最无用的注释之一。你可以像这样修剪空白：

query=query.trim（）；