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Distributed application in a LAN with one DB server

I plan on making a distributed application where 10-15 computers are connected in a LAN and there is one server where the database will be stored, also inside the LAN.
For the purpose of the question lets say the application will be made using Java and the database will be MySQL, but that is not yet decided.
So the question is, what do I need to realize this?
I have ofcourse worked with MySQL databases, but on a single computer so I am not quite sure how to connect the computers to the database server. Is it enough to setup the server local IP on all client computers and connect to it using the JDBC MySQL driver, and after that I can work with it like the DB is on my machine?
Also, do I need a server application to manage connections to the database, so that there are no conflicting entries? And if I do, then the connection part changes, because it needs to be established over the server application, so how do I do that?
I know it is a large question, but a lot of things seem unclear, because I have never attempted a project this big.
Thank you all!

Don't worry just made your application, you can connect to your database via an #IP, so just make a part of configuration in your application to change some information in future:
String db_url = "jdbc:mysql://192.168.0.1/db_test";
Is it enough to setup the server local IP on all client computers and
connect to it using the JDBC MySQL driver, and after that I can work
with it like the DB is on my machine
You don't need a server local of every computer, you can connect to the server directly.
Also, do I need a server application to manage connections to the
database, so that there are no conflicting entries? And if I do, then
the connection part changes, because it needs to be established over
the server application, so how do I do that?
If you are using a desktop application, the you don't need a server application, else if you are using a web application, yes you need one.
You need to shouse a server application, this dippend of your project or your company, there are free servers like GlassFish, Payara, Apache Tomcat, Wildfly and more.
Now the connection to your database, there are many ways to connect to your database, if you are using JPA to connect to your database, then you will hear
something about Entities, Facades, JNDI so this generally be configure in your server
application.
Hope you get an idea.

Java: How to connect to mysql and redhsift hosted in AWS?

I am trying to do some automation in mysql and redshift usin Java (JDBC) preferred. I usually use a remote desktop connection to connect, from there I use mysql workbench and aginity workbench to access mysql and redshift repectively. I have authentication for both as well as the aws urls.Also the aginity license. My goal is to connect Java running outside the remote desktop, to query some data fro mthe databases and compare them. I would like to know how to connect to both databases, as well as the documentation where I can learn more. I familiar with all three technologies , I just now sure how to connect them together. I am lost ,kidnle help. Thanks in advance.

H2 Database Auto Server mode : Accessing through web console remotely

I am fairly new to H2 Database. As a part of a PoC, I am using H2 database(version : 1.4.187) for mocking the MS SQL Server DB. I have one application, say app1 which generates the data and save into H2. Another application, app2, needs to read from the H2 database and process the data it reads. I am trying to use Auto Server mode so that even if one of the application is down, other one is able to read/write to/from the database.
After reading multiple examples, i found how to build the h2 url and shown as below:
jdbc:h2:~/datafactory;MODE=MSSQLServer;AUTO_SERVER=TRUE;
Enabled the tcp and remote access as Below:
org.h2.tools.Server.createTcpServer("-tcpAllowOthers","-webAllowOthers").start()
With this, I am able to write to the database. Now, I want to read the data using the h2-web-console application. I am able to do that from my local machine. However, I am not able to understand how I can connect to this database remotely from another machine.
My plant is to run these two apps in an ubuntu machine and I can monitor the data using the web console from my machine. Is it not possible with this approach?
How can I solve this ?
Or do I need to use server mode and explicitly start the h2 server? Any help would be appreciated.

By default, remote connections are disabled for H2 database for protection. To enable remote access to the TCP server, you need to start the TCP server using the option -tcpAllowOthers or the other flags -webAllowOthers, -pgAllowOthers
.
To start both the Web Console server (the H2 Console tool) and the TCP server with remote connections enabled, you will have to use something like below
java -jar /path/to/h2.jar -web -webAllowOthers -tcp -tcpAllowOthers -browser
More information can be found in the docs here and console settings can be configured from here

Not entirely sure but looking at the documentation and other questions answered previously regarding the same topic the url should be something like this:
jdbc:h2:tcp://<host>:<port>/~/datafactory;MODE=MSSQLServer;AUTO_SERVER=TRUE;
It seems that the host may not be localhost and the database may not be in memory

Is there a need for the H2 web console?
You can use a different SQL tool using the TCP server you have already started. I use SQuirreL SQL Client (http://squirrel-sql.sourceforge.net/) to connect to different databases.
If you need a web interface you could use Adminer (https://www.adminer.org/) which can connect to different database vendors, including MS SQL, which happens to be mode you're running H2. There is an Adminer Debian package that should work for Ubuntu.

How to Connect with MySQL Database File( .sql ) using Directory Path Like MS Access?

Sorry Maybe this is the second time I am Asking this question because of not getting any answers .
this is my Code
try{
File f = new File("Database.sql");
if(f.exists()){
Class.forName("com.mysql.jdbc.Driver").newInstance();
Connection con = DriverManager.getConnection("jdbc:mysql://localhost/"+f.getName(),"","");
}else{
f.createNewFile();
System.out.println("file created");
//also do the connection
}
}catch(Exception ex){
System.out.println(ex.getMessage());
}
and Here is the error :
Communications link failure
The last packet sent successfully to the server was 0 milliseconds ago. The driver has not received any packets from the server.
The purpose of this question is:
I am creating an Application that is for many users, the problem is they don't know anything about computer and I must make it as simple as possible.
So is there any way to connect with MYSQL like MS ACCESS via Directory Path ?
OR is there any other suggestion instead ?
Thanks .

AFAIK, you can't plug in a file name in the JDBC url for MySQL. MySQL needs to be running, and you need to connect to it via its TCP port. Something like:
jdbc:mysql://localhost:3306/yourDatabaseName
See http://dev.mysql.com/doc/refman/5.6/en/connector-j-reference-configuration-properties.html

Preliminary definitions
"Connect to a MySQL database file" is improper phrasing.
One actually connects to a MySQL database server, which allows access to a database. And so there must be a MySQL server to connect to, more about that below.
Your Database.sql file is a database dump file, that is to say, a dumb (plain text) file. You need a specialized process to extract data from it, after interpreting your SQL queries: a database server.
You might be assuming that one can connect to a file because you are used to working with MS Access files. I am not an expert neither in Java nor in MS Access, but it is my undestanding that accessing a MS Access "database" file from Java actually means connecting to some middleware server, such as this ODBC thingy from Microsoft.
The answer
There is no way to connect to a MySQL database server via a directory path. The only native ways are:
TCP
Local socket (Unix servers only)
Named pipes (Windows servers only)
Shared memory (Windows servers only)
There could be some third-party pieces of software around that provide other protocols, which I am not aware of, but they all reduce to the same problem: there must be a MySQL sever running somewhere.
On second thought there is actually one way to access MySQL data without an external MySQL server running: the embedded MySQL server C library. I never tried it myself, but it looks like a viable option for stand-alone applications. I do not believe, however, that it is a desirable solution if you plan to share the same MySQL data across several processes or computers.
The workarounds
Now I understand you are building a Java desktop application based on data that you have in the form of a SQL dump file, probably dumped from a MySQL server. If you want your users to be able to access this data from this Java application, I can see a few options:
Install a MySQL server on their computers and load this dump into it. Obvious as hell, but impractical, if I hear you well. Although I guess this installation could certainly be performed automatically by your Java application.
Install a MySQL server on a machine of your own, and make it accessible from your users' computers. Major drawback: it requires your users to be connected. You would also probably want to create a distinct database for each user.
Use an actually serverless database engine such as SQLite. This seems to be the best option for you. Its SQL syntax is virtually identical to MySQL for usual operations. There must be plenty of JDBC drivers for it. Again, I am not the best advisor in Java, but this one seems to be a serious candidate.

Whats my hostname on my local MySQL server?

I just set up a MySQL server on my PC for testing Java with JDBC.
At the moment "localhost" works perfectly as hostname for my applications, when running them on the same system.
However what would be the hostname for my MySQL server for applications that are running on different computers? Something like "my_ip:port" would work? I was thinking of writing an applet, which I could upload on a web server and try to connect to my database here. Is it possible to achieve that?

Something like "my_ip:port" would work?
If the MySQL instance has bound to your public interface, and if your firewall allows it, yes. If you connect to the 'net via a router that does NAT (for instance, a combined DSL modem and wireless router allowing you to connect multiple computers), you'll have to set up forwarding rules in the router to tell it which of the local machines to forward requests to.
You don't have to use an IP address. Your machine will also probably have a host name of some kind (either one you've assigned or, if you connect through an ISP, more likely one they've assigned). That would work too.
I was thinking of writing an applet, which I could upload on a web server and try to connect to my database here. Is it possible to achieve that?
With a signed Java applet, yes; otherwise, no. That's because the security sandbox that Java applets run in doesn't let them access servers other than the one they were loaded from (the web server).
A much better approach is to have your client-side code (Java applet, or just DHTML+Ajax stuff) talk to server-side code on the web server, which in turn talks to your DB. That way, the DB is never directly exposed to the outside world, and you don't have to do things like signed applets.

You can always use the ip address of the server running mysql as the hostname or its fully qualified domain name.

That should work, but you also should consider port-forwarding through your firewall.
Go here to get your IP: http://www.whatsmyip.org/
The port is the port mysql is setup on.