"PHP" MySQL basic operation integration

PHP Versions: PHP version 5.5.1

Environment: WINDOWS10 Xmapp

Database: MySQL

Code:

<?PHPfunctionCONNETIONDB ($servername,$username,$password,$db) {   //Create a connection    $conn=Mysqli_connect($servername,$username,$password,$db); //Detecting Connections    if(!$conn) {         die("Connection failed:".)Mysqli_connect_error()); return FALSE; }    return $conn;}//Create a databasefunctionCREATE_DB ($dbname,$conn) {     $sql= "CREATE DATABASE"$dbname‘"; if(Mysqli_query($conn,$sql)) {         Echo"DB created successfully"; }Else {         Echo"Error:".Mysqli_error($conn); }}//New TablefunctionCreate_table ($conn) {    $sql= "CREATE TABLE account (ID INT (6) UNSIGNED auto_increment PRIMARY KEY, username VARCHAR (+) not NULL, PASSW Ord VARCHAR (+) not NULL)"; if(Mysqli_query($conn,$sql)) {        Echo"Table created successfully"; }Else{        Echo"Error:".Mysqli_error($conn); }}//Inserting DatafunctionInsert$username,$password,$conn){    $sql= "INSERT into account (username, password) VALUES ('$username‘, ‘$password‘)"; if(Mysqli_query($conn,$sql)) {        Echo"Insert successfully<br>"; }Else{        Echo"Error:".Mysqli_error($conn); }}//Querying DatafunctionGet$username,$conn) {    $sql= "Select password from account WHERE username = '$username‘"; $result=Mysqli_query($conn,$sql); if(!$result) {        printf("Error:%s\n",Mysqli_error($conn)); Exit(); }     while($row=Mysqli_fetch_array($result)) {//echo "Username:". $username. "Password:". $row [' Password '];//echo ' <br> ';        return $row[' Password ']; }}//Delete DatafunctionDelete$username,$password,$conn) {    $sql= "DELETE from account WHERE username = '$username' and password = '$password‘"; if(Mysqli_query($conn,$sql)) {        EchoThe Delete$usernameSuccessfully<br> "; }Else{        Echo"Error:".Mysqli_error($conn); }}//Update DatafunctionUpdate$username,$password,$new _username,$new _password,$conn) {    $sql= ' '; if($new _username= = "and$new _password! = ") {        $sql= "UPDATE account SET Password = '$new _password' WHERE username = '$username' and password = '$password‘"; }Else if($new _username! = "and$new _password= = "'){        $sql= "UPDATE account SET username = '$new _username' WHERE username = '$username' and password = '$password‘"; }Else if($new _username! = "and$new _password! = "){        $sql= "UPDATE account SET username = '$new _username', password = '$new _password' WHERE username = '$username' and password = '$password‘"; }    if(Mysqli_query($conn,$sql)) {//echo "Update successfully";        return true; }Else {//echo "Error:". Mysqli_error ($conn);        return false; }}//Close ConnectionfunctionClosedb ($conn) {    Mysqli_close($conn);}

Use: direct include "db.php" can call the method in this.

"PHP" MySQL basic operation integration