PHP：查询说表在初始加载时不存在，但在此之后存在

Question

我现在已经运行了这个代码大约一个星期了，直到今天才解决这个问题。当我第一次加载我的网页时，初始化数据库并创建表（如果它们中的任何一个尚不存在）。但是，在同一个HTML页面上，我调用了一个Javascript函数来创建数据库中的数据表。此函数调用生成一个错误，表示数据库中不存在该表，但是我登录到WAMP并且表存在，并且在后续加载（数据库已经存在）中，该函数正常工作。这里出了什么问题？

actions.js：

$(document).ready(function() {

    $.ajax({
        url: "action.php",
        type: "GET",
        data: { param1: "INITIALIZE"}
    });

    var json = [];

    //Function for getting decks from database
    function getDecks(hide) {
        $.ajax({
            url: "get_decks.php",
            type: "GET",
            data: {hideDecks : hide},
            success: function(data) {
                alert(data);
                json = JSON.parse(data);
                if(hide == "TRUE") {
                    createTable();
                } else {
                    createHideDeckTable();
                }
            }
        });
    }
}

action.php的：

define("SERVER_NAME", "localhost");
define("USERNAME", "root");
define("PASSWORD", "");
define("DATABASE", "flashcards");
define("CHAPTERS_TABLE", "chapters");
define("DECKS_TABLE", "decks");
define("CARDS_TABLE", "cards");

//Function to execute database queries
function executeQuery($sql_query) {
    //Connecting to database
    $mysqli = mysqli_connect(SERVER_NAME, USERNAME, PASSWORD, DATABASE);

    //Check database connection
    if($mysqli === false) {
        die ("\nCould not connect:  " . mysqli_connect_error());
    }

    $result = mysqli_query($mysqli, $sql_query);

    if($result === false){
        echo nl2br("\n\nERROR: Could not able to execute $sql_query. " . mysqli_error($mysqli));
    }

    //Close database connection
    mysqli_close($mysqli);
}

//Function to execute database queries and return the result
function executeQueryWithResult($sql_query) {
    //Connecting to database
    $mysqli = mysqli_connect(SERVER_NAME, USERNAME, PASSWORD, DATABASE);

    //Check database connection
    if($mysqli === false) {
        die ("\nCould not connect:  " . mysqli_connect_error());
    }

    $rows = [];
    $result = mysqli_query($mysqli, $sql_query);

    if($result === false){
        echo nl2br("\n\nERROR: Could not able to execute $sql_query. " . mysqli_error($mysqli));
    } else {
        while($row = mysqli_fetch_assoc($result)) {
            $rows[] = $row;
        }
        return $rows;
    }

    //Close database connection
    mysqli_close($mysqli);
}

//This function initializes the database and all tables in the database
function initializeDatabase() {
    $mysqli = mysqli_connect(SERVER_NAME, USERNAME, PASSWORD);

    //Check database connection
    if($mysqli === false) {
        die ("\nCould not connect:  " . mysqli_connect_error());
    }

    //Query to create flashcards database
    $sql = "CREATE DATABASE IF NOT EXISTS " . DATABASE;
    mysqli_query($mysqli, $sql);

    //Set flashcards database as default database
    mysqli_select_db($mysqli, DATABASE);

    //Create the "Chapters" table
    $sql_create_chapters_table = "CREATE TABLE IF NOT EXISTS " . CHAPTERS_TABLE . "(
        chapter_ID INT NOT NULL PRIMARY KEY AUTO_INCREMENT,
        name VARCHAR(255) NOT NULL UNIQUE
        )";
    executeQuery($sql_create_chapters_table);

    //Create the "Decks" table
    $sql_create_decks_table = "CREATE TABLE IF NOT EXISTS " . DECKS_TABLE . "(
        deck_ID INT NOT NULL PRIMARY KEY AUTO_INCREMENT,
        chapter_ID INT NOT NULL,
        deck_description VARCHAR(255) NOT NULL,
        faculty BOOLEAN NOT NULL,
        hidden BOOLEAN NOT NULL,
        FOREIGN KEY (chapter_ID) REFERENCES chapters(chapter_ID)
        )";
    executeQuery($sql_create_decks_table);

    //Create the "Cards" table
    $sql_create_cards_table = "CREATE TABLE IF NOT EXISTS " . CARDS_TABLE . "(
        card_ID INT NOT NULL PRIMARY KEY AUTO_INCREMENT,
        deck_ID INT NOT NULL,
        front_text VARCHAR(255) NOT NULL,
        front_media VARCHAR(255),
        back_text VARCHAR(255) NOT NULL,
        back_media VARCHAR(255),
        FOREIGN KEY (deck_ID) REFERENCES decks(deck_ID)
        )";
    executeQuery($sql_create_cards_table);

    //Close database connection
    mysqli_close($mysqli);
}

//Process GET request
if(isset($_GET["param1"])) {
    $arg = $_GET["param1"];
    //"INITIALIZE" means database and tables should be created
    if($arg == "INITIALIZE") {
        initializeDatabase();
    }
}

get_decks.php：

include "action.php";

$sql_query = "SELECT * FROM " . DECKS_TABLE . " JOIN " . CHAPTERS_TABLE . " ON " . CHAPTERS_TABLE . ".chapter_ID=" . DECKS_TABLE . ".chapter_ID";

//Check whether or not hidden decks should be returned by the query
if(isset($_GET["hideDecks"])) {
    if(strcmp($_GET["hideDecks"], "TRUE")==0) {
        $sql_query .= " WHERE hidden=\"0\"";
    }
}

$rows = executeQueryWithResult($sql_query);
echo json_encode($rows);

的index.html：

<!DOCTYPE html>
<html>
<head>
    <title>My Application</title>
    <script src="https://ajax.googleapis.com/ajax/libs/jquery/3.1.0/jquery.min.js"></script>
    <script src="actions.js" type="text/javascript"></script>
</head>
<body>
    <h1 align="center">WELCOME TO MY APPLICATION</h1>
    <script>getDecks("TRUE");</script>
</body>
</html>