I have created a Web Application using Java JSP and for a Database I used MySql server 5.5. I am running on windows and the application works just fine. My question is, where is the actual physical database stored, i can not find it anywhere on my computer, and the reason why i am asking is portability, if i copy and paste and run the project on different machine, there is a problem connecting to the database, i can recreate the schema of the database, but the actual data stored in the database i can not find it.
Please help
Use mysqldump to backup your database:
The mysqldump client is a backup program originally written by Igor
Romanenko. It can be used to dump a database or a collection of
databases for backup or transfer to another SQL server (not
necessarily a MySQL server). The dump typically contains SQL
statements to create the table, populate it, or both. However,
mysqldump can also be used to generate files in CSV, other delimited
text, or XML format.
An alternative option if you don't want to use the commandline is to use a program like HeidiSQL
Related
I successfully connected to a DB in eclipse through the Database Development perspective and am able to run queries in the SQL File Editor. However, I would like to write java code to automatically run a query and then extract the data to a flat file. What is the easiest way to do this? Since I am already connected to the database, can I bypass the java code that involves connecting to the database.
No, the Java JVM also needs to be able to connect to the database. There are many examples of JDBC connections on the internet, including this one.
Once you have got the data you needed, you should make use of FileWriter in order to write the information to file.
I am trying for a while to make executable JAVA application having embedded DB (derby DB), but facing some problems, and need your valuable help.
Namely, I am using Eclipse as environment.
I export Java app to RUNNABLE JAR file, and it works fine on my desktop machine.
The idea is to make EXE doubleclick icon and send it to another machine which have no JAVA background/environment....so point is to send it to another user who will just get exe file, double click it and work with it.
The DB is not only readable, since application is inserting data in tables.
So, it works fine on my machine, but when I send the same JAR file to another machine, I get error:
"Schema TEST does not exist"
I can see application but without any data, like there is no connection with DB. So, it is useless.
Even I use JSmooth, Install4j.... to convert JAR to exe file, I get the same error.
So, first I have to make JAR file working on another machine.
Seems to me, I am doing something wrong with DB files.
Please let me know what info u need more from my side, and let me know how I can do this.
If the application intends to read AND WRITE data when it is running, then it can't be entirely contained in a JAR file, because you can't put an updatable Derby database in a JAR file. You'll need to have some "installation procedure", perhaps some logic that you run the first time your application is double-clicked by the user, that (a) finds a suitable location for the Derby database on the user's machine, (b) creates the database and defines all the tables, views, etc, (c) loads any initial data.
Then, on subsequent runs of the application, it will be able to re-open the database and continue using it.
Short Version: I need to store some data between runs of a java program.The data will be of the form of a table.Is there anything that can let do something like a sql query in java??THE SOLUTION MUST BE ABLE TO RUN ON AN OFFLINE COMPUTER.
Long Version: The user will be entering some data daily and i want something like a sql table in java. The program will run on a computer that is NOT CONNECTED TO THE INTERNET and so i need a truly local way to store data(Lots of it).Also preferably the data should be stored in such a way that it is not easily accessible to the end user(as in ,he should not be able to double click the file and simply read its contents)
Major Constraint: On searching online i found many people were using localhost to solve similar problems but that facility is not available to me as i CANNOT INSTALL ANYTHING on the target computer.
If a simple data file is not good enough, how about using SQLite with a JDBC backend? It will allow you to have an SQL database stored in a regular file with no dependency on any kind of server. Alternatively, there are many other embedded DB engines that you could use, depending on your needs.
EDIT:
By the way, most (if not all) DB engines that I know of do not obfuscate the data before storing them in the filesystem. The data will be fragmented, but parts of it will be visible if you force an editor to open the file (e.g. using "Open with..." in Windows).
There is also nothing to stop your user from accessing the data using the command line utility of the selected DB engine. If you want to obfuscate the data you have to do it in your code. Keep in mind that this will not stop a determined person - if your application can read it offline, so can everyone else.
Use an embedded database (like Apache Derby, HSQLDB, H2) so that you don't have to run a database server on the machine. The data will be stored locally on the target machine and it won't be human readable.
You have several options:
Store it in an xml-file
Store it in an local installed database
You can install a database like mysql or use a in memory database like sqlite or hbase or apache derby, which is included in java 6
I have set up mysql database to run with java and eclipse on my Mac, it is running great, but now I will generate aprox 4.3billion rows of data which will take up approx 64gbs of data, I'm storing a large about of keys and encrypted values, I have a 1TB external i would like to use as a storage location, i first thought i could reinstall mysql onto the external but it no luck as it obviously isnt running mac osx, Is there anyway i Can point mysql to store a database on the external, i have done some searching but have not come across an answer yet.
I am running Java to build and query the databse and Table if this comes into play.
Thanks.
Find your mysql config file (typically called my.cnf). Change the database path.
http://dev.mysql.com/tech-resources/articles/mysql_intro.html#SECTION0001500000
Don't reinstall mysql. You should use both the hdd and the external hard to store the data (rows/tables..) for mysql server.
Maybe by changing the path, but I haven't tried that.
I'm considering using HSQLDB version 1.8.x in a desktop app for storing local data. From what I can see, the database is stored on disk as a number of SQL statements to create the tables, insert the data, etc.
Is there a simple way I can hide this from users? I'm don't necessarily need it to be completely encrypted, etc - I'd just like to prevent the casual user from simply opening the file and seeing the structure of the database.
You could embed your database files within a jar file and connect to them using the notation:
jdbc:hsqldb:res:<path in jar>
Check out the Advanced Topics section of the HSQLDB guide for more information on this. However, I've never tried it so am not 100% sure it will work ...
The solution I've gone with for now is to call:
db.update("SET SCRIPTFORMAT COMPRESSED;");
to store the .script file in a human-unreadable form and:
db.update("SET PASSWORD password;");
to prevent more savvy users from opening the DB using their own HSQLDB client.
Unfortunately I was not able to execute below command
db.update("SET scriptformat COMPRESSED");
And was getting this error
java.sql.SQLSyntaxErrorException: user lacks privilege or object not found: SCRIPTFORMAT
This error solved with this command
db.update("SET FILES SCRIPT FORMAT COMPRESSED");
I am using HSQLDB 2.3.3