How to connect Tomcat9 to a MySQL database and access the database in eclipse using Vaadin14? I already pasted the mysql connector in the tomcat\lib directory. Is there anything else to do/change?
Afterwards i created a ui that contains a few text fields and a java class car with some attributes and the corresponding getters/setters. I bound the text fields to the attributes using a binder. In my database there is also a table car with the same attributes and some entries.
So how do i connect the database to my project in order to show one of the entries in my text fields and create a new entry?
Sorry if this is basic java/vaadin, but i'm quite new to databases.
So how do i connect the database to my project in order to show one of the entries in my text fields and create a new entry
You first need to connect to a database. It depends on your project, how you implement it. (via Spring, for example). A good discussion on this topic is here: Connect Java to a MySQL database
and some documentation here Connecting to MySQL Using the JDBC DriverManager Interface
Then you read data you need from a database. You can use ORM such as Hibernate or use a JDBC package as this. A discussion on pros/cons can be found here: What Java ORM do you prefer, and why?
Once you have your data available, you can bind an object to the binder (if you use one) or using setValue for the fields. There is an example for Vaadin 8 here : Building a web UI for MySQL databases (in plain Java), but it should be applicable with a Vaadin 14 as well. (Or what is your version?)
You could also check a bakery starter and how connection/reading is implemented there.
Some other useful links on topic:
What is JPA? Introduction to the Java Persistence API
Vaadin app with MySQL database
Related
I have a simple Quarkus application that uses an in-memory H2 database. The JDBC connection string has some custom settings: jdbc:h2:mem:quarkus_db;DATABASE_TO_LOWER=TRUE;DB_CLOSE_DELAY=-1;MODE=MariaDB.
I'm trying to connect to the exact same database from a database manager — say DataGrip. After following the documentation, several answers from StackOverflow, and some blog posts, I'm still unable to connect to the same instance and query for any existing data using SQL.
There is something I don't fully understand from the examples. I've seen that initially using a connection like this in the application: jdbc:h2:mem:quarkus_db, and while the same it's up and running, then on the other application/process (DataGrip in my case) using jdbc:h2:tcp://localhost/mem:quarkus_db should work, but I fail to see how the first scheme will create a TCP server.
My goal is to verify some data while the application is running. I understand that when using something like jdbc:h2:mem:*, everything will be lost after the application stops.
Neo4j have recently added a BI connector tool (neo4j.com/bi-connector) which can return relational data from your graph database to your business intelligence tool such as Tableau. The question is can i send SQL queries to this connector assuming i have added the jar file to my java application class path? If yes, which APIs should i use to send this SQL query to the driver?
I'm using Neo4j4.0.
For neo4j.com/bi-connector, if you look at the document PDF that you get when you download it, on page 10 where they show how to establish a connection you'll see that you get a connection object. After you have that, you have a standard JDBC connection which is a Java interface that tells libraries how to talk to a SQL database. There are a lot of different tools that use this interface, it's kind of user preference. A common one is JOOQ.
I am developing a Java application in play framework and the back end of the application is Oracle. My database does not have a SID instead, it uses service ID. Also I am using Ebean in the application. This is my connection information in application.conf file.
db.default.url="jdbc:oracle:thin:#HOST:PORT/SERVICE_NAME"
db.default.user=USERNAME
db.default.pass=PASSWORD
Where I can specify the database name?
when you insert correct information about ip port and db schema it should work fine. The one thing that it missing here is:
db.default.driver=oracle.jdbc.driver.OracleDriver
I want to create a Desktop App(Software), preferably in Java, which connects to a central MySQL DB on a local network whenever available.
I also want it to store and use a copy of the same DB when the central DB is not available, and sync whenever the central DB is available.
How can I store data locally, I mean which kind of database should I use for local database?
Also, are there any tools which speed up the Desktop App development?
Let's suppose that you will implement your solution in Java. You will need some classes (i.e. Data Access Obejcts, DAOs) in charge of interacting with the database on the network and on a file based database embedded in the application (the "local" database).
What you need:
A local database that you can ship with your application like H2 www.h2database.com, HSQLDB http://hsqldb.org/ or Derby db.apache.org/derby/.
To develop your DAOs (using JDBC or Hibernate) in such a way that you can instantiate them with different drivers, URLs, login/pwd and use only SQL standard / functions supported both by MySql and by the local DBMS. In practice you must avoid using DB specific functions.
You can use Hibernate or JPA for example, they have quite a nice and easy integration with your application.
I need to make an application where the user can configure some connection parameters like server and DBMS (specifically MySQL, MSSQL and Oracle). As long as the database schema is the same, but not the server in order to use the servers already working in the client's intranet, I'm trying to find a way to force jpa use the parameters set by the user and make the transaction.
Any idea?
Use the property file contains information about the DB, username and password which will change according to the d