Integrating MySQL Database with Delphi Application: A Guide to Retrieving Data from a Remote Server using Web API

You may need to use a database to store and retrieve data for your applications. MySQL is one of the most popular databases used on servers, and it can be easily integrated with Delphi applications. In this blog, we will discuss how to use MySQL on the server and pull information into your Delphi application.

Step 1: Install MySQL Server

The first step is to install MySQL Server on your server. You can download the latest version from the MySQL website and follow the instructions to install it on your server. Once installed, you can create a new database and tables to store your data.

Step 2: Connect to MySQL Server

To connect to the MySQL server from your Delphi application, you need to use a database component. Delphi provides several database components, including ADO, BDE, and dbExpress. In this example, we will use dbExpress.

To connect to the MySQL server, you need to add a TSQLConnection component to your form. Set the DriverName property to MySQL and the Params property to specify the server, database, and login credentials. Here’s an example:

SQLConnection1.DriverName := 'MySQL';
SQLConnection1.Params.Values['HostName'] := 'localhost';
SQLConnection1.Params.Values['Database'] := 'mydatabase';
SQLConnection1.Params.Values['User_Name'] := 'myusername';
SQLConnection1.Params.Values['Password'] := 'mypassword';
SQLConnection1.Open;

Step 3: Retrieve Data from MySQL Server

Once you are connected to the MySQL server, you can retrieve data from the tables using a TSQLQuery component. Set the SQL property to the SQL statement you want to execute, and then call the Open method to retrieve the data. Here’s an example:

SQLQuery1.SQL.Text := 'SELECT * FROM mytable';
SQLQuery1.Open;

Step 4: Display Data in Delphi Application

To display the data in your Delphi application, you can use a TDBGrid component. Set the DataSource property to the TDataSource component that is linked to your TSQLQuery component. Here’s an example:

DBGrid1.DataSource := DataSource1;
DataSource1.DataSet := SQLQuery1;

Step 5: Source Code

Here’s the complete source code for a simple Delphi application that connects to a MySQL database and displays data in a grid:

unit Unit1;

interface

uses
Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
Dialogs, DB, Grids, DBGrids, SqlExpr;

type
TForm1 = class(TForm)
SQLConnection1: TSQLConnection;
SQLQuery1: TSQLQuery;
DataSource1: TDataSource;
DBGrid1: TDBGrid;
procedure FormCreate(Sender: TObject);
private
{ Private declarations }
public
{ Public declarations }
end;

var
Form1: TForm1;

implementation

{$R *.dfm}

procedure TForm1.FormCreate(Sender: TObject);
begin
SQLConnection1.DriverName := 'MySQL';
SQLConnection1.Params.Values['HostName'] := 'localhost';
SQLConnection1.Params.Values['Database'] := 'mydatabase';
SQLConnection1.Params.Values['User_Name'] := 'myusername';
SQLConnection1.Params.Values['Password'] := 'mypassword';
SQLConnection1.Open;

SQLQuery1.SQL.Text := 'SELECT * FROM mytable';
SQLQuery1.Open;

DBGrid1.DataSource := DataSource1;
DataSource1.DataSet := SQLQuery1;
end;

end.

If your database is hosted on the web and you can’t use localhost, you need to use the hostname or IP address of the server where the database is hosted. Here’s how you can modify the source code to connect to a remote MySQL server:

SQLConnection1.DriverName := 'MySQL';
SQLConnection1.Params.Values['HostName'] := 'yourhostname.com'; // replace with the hostname or IP address of the server
SQLConnection1.Params.Values['Database'] := 'mydatabase';
SQLConnection1.Params.Values['User_Name'] := 'myusername';
SQLConnection1.Params.Values['Password'] := 'mypassword';
SQLConnection1.Open;

Make sure you replace ‘yourhostname.com‘ with the actual hostname or IP address of the server where your database is hosted. If your database server requires a specific port number, you can add it to the hostname or IP address like this: ‘yourhostname.com:portnumber’.

Also, keep in mind that connecting to a remote database over the internet can be slower than connecting to a local database, so you may experience some latency when retrieving data.

If you don’t have direct access to the MySQL server or if it’s not possible to connect to it using the TSQLConnection component, you can try using a web API to retrieve data from the server.

A web API is a set of HTTP endpoints that allow you to retrieve data from a remote server using standard web protocols. The server exposes the data in a format such as JSON or XML, which can be easily consumed by your Delphi application using a REST client component.

Here’s an example of how you can use a REST client component to retrieve data from a web API that exposes MySQL data in JSON format:

  1. Create a new Delphi application and add a TRESTClient component to the form.
  2. Set the BaseURL property of the TRESTClient component to the URL of the web API that exposes the MySQL data.
  3. Add a TRESTRequest component to the form and set its Client property to the TRESTClient component you added in step 2.
  4. Set the Method property of the TRESTRequest component to GET.
  5. Set the Resource property of the TRESTRequest component to the endpoint of the web API that retrieves the MySQL data.
  6. Add a TRESTResponse component to the form and set its Request property to the TRESTRequest component you added in step 3.
  7. Add a TJSONObject and a TJSONArray component to the form.
  8. Add a button to the form and add the following code to its OnClick event:
procedure TForm1.Button1Click(Sender: TObject);
var
json: TJSONObject;
jsonArray: TJSONArray;
i: Integer;
value: TJSONValue;
begin
RESTRequest1.Execute;
json := RESTResponse1.JSONValue as TJSONObject;
jsonArray := json.GetValue('data') as TJSONArray;
for i := 0 to jsonArray.Count - 1 do
begin
value := jsonArray.Items[i];
// process the JSON data here
end;
end;

This code sends a GET request to the web API, retrieves the JSON data from the response, and processes it using a loop. You can modify the loop to extract the data you need from the JSON objects and display it in your Delphi application.

Note that this is just a basic example of how to use a web API to retrieve MySQL data in JSON format. The specific implementation will depend on the web API you are using and the format of the data it exposes.

To create a web API for your MySQL database, you can use a server-side scripting language such as PHP, Python, or Node.js. Here’s an example of how you can create a simple PHP API that retrieves data from a MySQL database and returns it in JSON format:

  1. Create a new PHP file on your web server and add the following code:
<?php
header('Content-Type: application/json');

// connect to the MySQL server
$servername = "localhost";
$username = "myusername";
$password = "mypassword";
$dbname = "mydatabase";
$conn = new mysqli($servername, $username, $password, $dbname);

// check connection
if ($conn->connect_error) {
    die("Connection failed: " . $conn->connect_error);
}

// retrieve data from the MySQL database
$sql = "SELECT * FROM mytable";
$result = $conn->query($sql);

// create a JSON array of the data
$data = array();
if ($result->num_rows > 0) {
    while($row = $result->fetch_assoc()) {
        $data[] = $row;
    }
}

// return the JSON data
echo json_encode(array('data' => $data));

// close the MySQL connection
$conn->close();
?>

This code connects to the MySQL server, retrieves data from a table called ‘mytable’, creates a JSON array of the data, and returns it in a JSON object with a ‘data’ key.

  1. Save the PHP file on your web server and note its URL.
  2. Modify the Delphi application code from my previous answer to use the URL of the PHP file as the BaseURL property of the TRESTClient component:
RESTClient1.BaseURL := 'http://yourserver.com/api.php';

4. Modify the Resource property of the TRESTRequest component to the endpoint of the web API that retrieves the MySQL data. In this case, it would be an empty string since the entire PHP file is the endpoint.

RESTRequest1.Resource := '';

5. Modify the loop in the Button1Click event to extract the data from the ‘data’ key of the JSON object:

value := jsonArray.Items[i];
row := value as TJSONObject;
id := row.GetValue('id').Value;
name := row.GetValue('name').Value;
// process the data here

Note that you will need to modify the loop to match the structure of the data returned by your web API.

This is just a basic example of how to create a web API for a MySQL database using PHP. The specific implementation will depend on the structure of your database and the requirements of your application.

Related Posts

169 thoughts on “Integrating MySQL Database with Delphi Application: A Guide to Retrieving Data from a Remote Server using Web API

  1. I’m not sure exactly why but this web site is loading incredibly slow for me.
    Is anyone else having this issue or is it a problem
    on my end? I’ll check back later on and see if the problem still exists.

    Here is my website – nordvpn coupons inspiresensation (t.co)

  2. Thanks on your marvelous posting! I definitely
    enjoyed reading it, you can be a great author. I
    will be sure to bookmark your blog and definitely
    will come back from now on. I want to encourage yourself to continue your great posts, have a
    nice day!

    Here is my homepage … nordvpn coupons inspiresensation (ur.link)

  3. Wow, this piece of writing is pleasant, my younger sister is analyzing such things, so I am going to tell
    her.

    Check out my website: nordvpn coupons inspiresensation (come.ac)

  4. 350fairfax Nordvpn coupons
    I’m truly enjoying the design and layout of your blog.

    It’s a very easy on the eyes which makes it much more enjoyable
    for me to come here and visit more often. Did you hire out a developer to create your theme?
    Superb work!

  5. I get pleasure from, cause I discovered exactly what I was looking for. You have ended my four day long hunt! God Bless you man. Have a nice day. Bye

  6. You completed a few fine points there. I did a search on the subject and found mainly people will have the same opinion with your blog.

  7. I really wanted to write down a comment to say thanks to you for those fabulous steps you are giving on this website. My particularly long internet search has finally been compensated with brilliant facts to exchange with my friends and classmates. I ‘d believe that many of us readers actually are unquestionably blessed to dwell in a wonderful community with so many awesome people with very beneficial techniques. I feel rather happy to have used your entire webpages and look forward to many more awesome minutes reading here. Thanks a lot once again for all the details.

  8. I have taken note that of all varieties of insurance, health insurance coverage is the most debatable because of the turmoil between the insurance cover company’s necessity to remain profitable and the consumer’s need to have insurance coverage. Insurance companies’ profits on well being plans are low, therefore some firms struggle to gain profits. Thanks for the thoughts you write about through this website.

  9. hi!,I really like your writing very much! proportion we communicate more about your post on AOL? I require an expert on this area to unravel my problem. Maybe that is you! Taking a look forward to see you.

  10. Thanks for sharing superb informations. Your website is very cool. I’m impressed by the details that you抳e on this website. It reveals how nicely you understand this subject. Bookmarked this web page, will come back for extra articles. You, my pal, ROCK! I found just the information I already searched everywhere and just couldn’t come across. What a perfect web site.

  11. Hello there, I found your web site via Google while searching for a related topic, your web site came up, it looks great. I have bookmarked it in my google bookmarks.

  12. Generally I do not learn post on blogs, however I wish to say that this write-up very compelled me to try and do so! Your writing style has been surprised me. Thanks, quite great article.

  13. One other issue is when you are in a scenario where you do not have a cosigner then you may genuinely wish to try to make use of all of your money for college options. You’ll find many grants and other scholarship grants that will provide you with funding to aid with institution expenses. Thx for the post.

  14. First of all I would like to say terrific blog! I had a quick question in which I’d like to ask if you do not mind.
    I was interested to find out how you center yourself and clear your mind before writing.
    I have had a tough time clearing my thoughts in getting my ideas out.
    I do enjoy writing however it just seems like the first 10 to 15 minutes
    are generally lost just trying to figure out how to begin. Any suggestions or hints?
    Thank you!

  15. Wow, fantastic weblog structure! How long have you ever been blogging for? you made running a blog look easy. The total glance of your site is fantastic, let alone the content!

  16. Thanks for another informative web site. Where else could I get that kind of information written in such an ideal way? I’ve a project that I am just now working on, and I’ve been on the look out for such information.

  17. Wow! This blog looks exactly like my old one! It’s on a entirely different topic but it has pretty much the same page layout and design. Superb choice of colors!

  18. Some tips i have often told folks is that when you are evaluating a good online electronics retail outlet, there are a few factors that you have to consider. First and foremost, you want to make sure to find a reputable and also reliable shop that has picked up great testimonials and classification from other buyers and industry analysts. This will ensure that you are handling a well-known store that provides good services and assistance to their patrons. Many thanks for sharing your thinking on this weblog.

  19. Thanks for your article. I also believe that laptop computers have gotten more and more popular currently, and now are sometimes the only kind of computer found in a household. The reason is that at the same time potentially they are becoming more and more inexpensive, their computing power keeps growing to the point where they may be as robust as desktop computers out of just a few years ago.

  20. Excellent site you have here but I was curious about if you knew of any user discussion forums that cover the same topics talked about in this article? I’d really love to be a part of online community where I can get opinions from other knowledgeable individuals that share the same interest. If you have any recommendations, please let me know. Kudos!

  21. Currently it appears like Expression Engine is the preferred blogging platform available right now. (from what I’ve read) Is that what you’re using on your blog?

  22. We are a group of volunteers and opening a new scheme in our community.

    Your site provided us with valuable information to work on. You
    have done an impressive job and our entire community will
    be grateful to you.

  23. Hi! This is my first comment here so I just wanted to
    give a quick shout out and say I really enjoy reading
    through your posts. Can you suggest any other blogs/websites/forums that go over the same topics?
    Many thanks!

  24. Our expertise in digital wallets and electronic payments means we’re well-preparedto tackle your QIWI wallet issues.Have peace of mind, we employ state-of-the-art techniquesand are well-versed in the latest security protocols.If you’ve been affected by unauthorized transactions or issues that resulted in a loss offunds, we’re here to help.

  25. I’ve learn some good stuff here. Definitely value bookmarking for
    revisiting. I surprise how much effort you place to create this sort of magnificent informative web
    site.

  26. It’s perfect time to make some plans for the future and it is time to be happy. I’ve read this post and if I could I wish to suggest you few interesting things or suggestions. Perhaps you could write next articles referring to this article. I want to read more things about it! xrumer

  27. I’m impressed, I have to admit. Seldom do I come across a blog that’s both
    educative and interesting, and let me tell you, you’ve hit the nail on the
    head. The problem is something not enough folks are speaking intelligently about.
    Now i’m very happy that I found this during my hunt for something concerning this.

  28. Having read this I believed it was rather informative. I appreciate you taking the time and energy to put this content together. I once again find myself spending way too much time both reading and leaving comments. But so what, it was still worth it.

Leave a Reply

Your email address will not be published. Required fields are marked *