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App with derby database - client access needs changing to embedded?

I'm still rather new to java and I think I've started a project with a problem.
I created a job for a friend in which there are employees, shifts, sites and these needed to be loaded at the beginning.
I went looking for solutions and decided to use a Derby database. I've now programmed the Application and it works fine with the database. It loads all parameters and creates objects for handling,
Now I need to deploy my project to my friends computer so he can use it and I think I have the database set up wrong. I think I needed it to be embedded? so it goes with the application.
So my questions are what are my choices,
I read I can change the database to an 'embedded' one by making the database a class? I have no idea how to do this and maybe because I'm new to java, I'm finding all the write ups on this subject difficult to understand.
Alternatively I thought maybe I can install Derby separately and connect to that?
Or maybe I can drop the Derby idea and switch entirely to another database entirely,
I'm a bit confused over my choices here, basically I've built an application around an installation of Derby DB using this line to connect to it.
jdbc:derby://localhost:1527/SG_database
If someone can give me some 'Plain English' options here I would very much appreciate it.

To reconfigure your application to use Derby as an embedded database, all you have to do is change that JDBC Connection URL to jdbc:derby:SG_database, and change your CLASSPATH so that your program references derby.jar rather than derbyclient.jar. You should possibly add ;create=true to the end of that URL so that, the first time your friend runs your application, the database is created on their machine.
But yes, you have other choices, and without knowing a fair amount about your application it's hard to give you very detailed guidance.
When your friend is using the application, do you want you and your friend to be sharing the same set of data? Or is your application designed so that your data and your friend's data have nothing in common?
If you want to be sharing the data, then yes it will be important to have a single instance of the database, and both of you have to share it, in which case a client-server configuration can work quite well.
If you want to be two completely separate applications, with nothing shared, and each of you has your own copy of the data, then an embedded configuration can work quite well.
Perhaps you could simply try the embedded configuration, see how it behaves with your application, and then return here if you have a more specific question to ask?

Initializing an HSQLDB instance and then using it in an app

I am brand new to the concept of embedded databases and have chosen HSQLDB to be the embedded DB for my Java app. I think I am fundamentally not understanding something: nowhere do I see how/where to:
Define username/password credentials that must be used for connecting to a database
Creating a new database (e..g, db_myapp)
Creating tables for that new database
With a non-embedded ("normal") DB, I would first use a DB client to connect to the database, and CREATE the db_myapp DB as well as any tables it should have. My app would then expect those tables to exist at runtime.
But with HSQLDB, I have no such DB server to connect to, so I don't see how/where I can create these databases/tables/credentials ahead of time, before my app runs.
And maybe that's exactly what an "embedded" DB does; perhaps its an entire DB embedded inside a JDBC driver? In any event, I still need a way to accomplish the 3 things listed above.
The only thing I can think of is to run some initialization code every time that my app starts up. This code would check for the existence of these constructs, and if they don't exist, then it would create them.
There are several problems here:
This approach might work with databases and tables, but not the credentials I need on the JDBC Connection itself. How/where do I create those?
I'm not even sure if this is the right/normal approach to using an embedded HSQLDB; can someone confirm I'm on track (that is, the "check-to-see-if-it-exists-and-if-not-then-create" approach)?
What happens if I accidentally execute code that tries creating a new database/table eve when it already exists? Will HSQLDB just ignore it or will it blow out my existing DB/tables?

The short answer is that you're pretty much on the right track.
Connecting to the embedded database is really no different from connecting to a normal db server, except that the connection string is a bit different. This section has information on that. The thing is that you don't really have separate 'databases' to choose from, it's just specified in the connection string. For the connection:
Connection c = DriverManager.getConnection("jdbc:hsqldb:file:/opt/db/testdb", "SA", "");
This will give you a connection to an embedded database engine that persists the data in the file at /opt/db/testdb. The default username for an embedded database will always be 'SA' with no password. I honestly don't know if it'll work, but if you really need to set a different password, you can try executing ALTER USER SA SET PASSWORD <newPassword>. It'll probably work...
As far as creating tables and such, there's a couple of way of going about this, depending on whether the database will be persisted as a File or in memory. Often times, embedded dbs get used for pretty simple data, and so the tables get created by executing a statement right after initializing the connection. CREATE TABLE IF NOT EXISTS ... is the usual way of doing things. This allows you to create a table only if it doesn't already exist.
If you're working with a file-base database, then hsqldb gives you another option. Take a look at this documentation about accessing a database using their tools. This would allow you to create a file-base database ahead of time, and set things like username/password and setup all your tables. Then you can just copy over the resultant file to be used by your application. Then everything would be setup before your application connects to it.
So ultimately, you have the option to go either way. You can either have your application set everything up when the connection is initialized, or you can set it up manually ahead of time. My preference is to have the application set it up in code simply because then your table definitions are kept closer to the code that actually uses them. I haven't used an embedded database like that for really complex data, though, so I can't honestly say how well that scales.

Java Netbeans Derby database for embedded system dilema: create the database with Netbeans or with code?

I read a lot of posts like:
querying embedded database in netbeans using derby
But still I'm having trouble to understand embedded databases.
1) I create a Derby database on Netbeans and I can create tables, link the database to a form and submit the data and update the records with no problem.
2) The problem arises when I want to make the program portable. I apply Clean and Build, then copy the dist folder and also copy the libraries, database, etc ... but when running the program does not recognize the database
3) I read in several places that it is appropriate that the database is created by code using something like
String host = "jdbc: derby: // localhost: 1527 / EmployeesCreateTrue; create = true"
and not creating the database on Netbeans Service...
If I do this procedure with code the database is created but it does not appear or does not allow me to connect from NetBeans and I wish I could fix it to create tables from NetBeans and not from code.
4) I read manuals "how to import a database from Derby to NetBeans" and it doesn't work...
Question: What is the best way to create a database, tables and connect to NetBeans for the final application to be easily portable?
1) Create the database on Netbeans with the wizzard?
or
2) Just plain code on the application?

I don't understand precisely what you mean by "the database is created but it does not appear."
I think if you were to explain that precisely, the community could probably help you.
There are three common reasons for "table does not exist" when you think you've created the tables; I've explained those cases in this answer: Is it necessary to create tables each time you connect the derby database?
Please let us know more information about your situation so that we can help you better understand the behavior of your application.

I'm not 100% sure if this is your problem, but a lot of problems people seem to have with Netbeans and Derby seems to come from the fact that they don't set derby.system.home explicitly. When you don't, Derby stores databases in the current directory, and that is likely different when working in the IDE, either in the Services tab, or your own code, than when you execute your app's jar as a standalone program. So the advice (which you will also find in the manual) is: always set derby.system.home. An alternative would be to use full paths to the databases, but that rarely works well for a real application that is deployed on different machines.

I had the same problem --had the derby db in the services but the netbeans coded programs didn't access it. I solved it by adding the derby database (copy paste) to the package in the Files section. I use Windows 7. Once I did that, I was able use multiple tables (before netbeans just ignored secondary tables and only allowed me to use the primary table).

How to create users in collabnet?

I am working on collabnet subversion repository. I installed CollabNetSubversionEdge-4.0.6_setup-x86_64 software and I created users in Collabnet GUI to access my repository. And I and my users accessing my repository and everything is working fine.But,
Here my task is Insted of creating users in Collabnet Create users in Data base(MySql or Oracle) and make them to lo-gin from our DataBase to access collabnet
I googled a lot but I didn't get even a single answer for this one.May be this is not possible. If it possible please tell me how to achieve this one.Thank you very much.

Subversion passes off security to its servers. If you use Apache httpd (you don't specify), you can use whatever Apache configurations to do user access. The two most common is LDAP (which can connect to your Windows Active Directory server) and using a text based httpasswd to generate a user password file. I have not seen this with SQL, and I couldn't imagine why you'd want to use something so complex for something so simple -- unless you already store users in a SQL database.
If nothing else, you could have a crontab that would build the svn_access_file via a SQL query that runs it through httpasswd.
There is some information from Oracle on this, but I have never seen it done, and Apache httpd's documentation doesn't have specific directions.

Creating a new local database with Java

My aim is to create a local database that can be read and written to with Java. I have some experience with manipulating a local sqlite database with Python, and with interacting with existing networked databases on Microsoft Azure via VB.Net, but the Java formulation for creating a database is escaping me.
Most sources (like the JDBC Docs) seem to assume that you are accessing a database through a network protocol, or a database hosted on localhost. My desired implementation is to create and store the database in a file (or collection of files), so that it can be stored and accessed locally, without network connectivity (presumable through the "file:" protocol).
The JDBC Tutorial looks like it will be very useful once I am up and running, but is currently beyond my scope, since I don't even have an existing database yet.
Many sources have suggested solutions like H2, MySQL, Derby, or Hypersonic DB. However, I'm loath to install extensions (if that's the right term) for a number of reasons:
This project is initially intended to help me learn my way around Java - widening the scope of the project will dilute my experience with the "base" language and, probably, increase the temptation to engage in "cargo cult programming"
If this project does ever get distributed to other users (admittedly unlikely, but still!), I don't want to force them into installing more than the core of Java.
I simply don't know how to install extensions (add-ons? modules?) in Java - one baby-step at a time!
For similar reasons, installing Microsoft SQL Server would not be productive.
This answer looks close to what I'm aiming for; however, it gives the error:
java.sql.SQLException: No suitable driver found for jdbc:mysql://localhost/?user=root&password=rootpassword
and trying "jdbc:file://targetFile.sql" gives a similar error.
I've seen the term "embedded" database, which I think is a subset of "local database" (i.e. a local database is stored on the same system - an embedded database is a local database that is only used by a single application) - if I've got those definitions wrong, please feel free to correct me!

Most likely, the reason for which you are getting the error, is due to the fact that you are not registering the driver (using reflection...) before actually using it for establishing a connection and so on.
Presumably you will want to do something along the lines of Class.forName("driver")
and then cast that if necessary and then registering it in the DriverManager before calling the getConnection() method.
Here is a very useful link that might help you out in solving the issue:
http://www.kfu.com/~nsayer/Java/dyn-jdbc.html
However, if you really want to use a local database/file you might want to have a look at SQLite, that might be one way to go about it, although I recommend going for the MySQL approach, as it is a lot easier to configure and learn how stuff works with JDBC.
If you are still considering SQLite check this out:
Java and SQLite
I see you need some guidance in importing external .jar files into your code (i.e. 3rd party libraries like the ones you will be using for a JDBC driver). Are you using an IDE (e.g. Eclipse, Netbeans, etc.) or are you writing in a text editor and compiling manually?

A number of embedded pure Java databases appeared recently, which have a really simple interface, usually just java.util.Map, don't involve using JDBC or other SQL artifacts, and store their data in a single file or directory:
Chronicle Map
JetBrains Xodus
MapDB
The main downside is that most of such databases provide only the simples key-value model.

DBC can be used with any database that has a JDBC driver, which isn't necessarily a database in "network mode", it can be used with embedded databases as well.
Here are some Java and embeddable databases:
http://www.h2database.com/html/main.html
http://db.apache.org/derby/
http://hsqldb.org/

Java's JDK does not include any implementation of a database nor drivers to access it. It only provides JDBC as an abstraction to connect to a "database". Is up to you to include all the needed libraries in your code.
If you want to have a self contained code you can simply include the .jar file of a embeddable database in you classpath. That way you can create the instance of the database in your code and minimize the external dependencies.
You can find here a list of java embeddable databases
You can find here an example of how to embed HSQLDB in your code.