Guide Step 2 DB Model

Telosys User Guide - DB Model

This step describe how to create a new model from an existing database.

Before continuing ensure your home directory is defined and the project has been initialized.

Configure your database

Edit the databases.dbcfg XML file to define a new database configuration.

Launch the external editor with the edb (Edit DB) command in Telosys-CLI or if you are in your prefered editor (Atom, VSCode, etc) just open the databases.dbcfg file.

In databases.dbcfg add a new <db> tag with all the expected information (use the examples of databases configuration available in the commented lines of the file).

For each database you must define the following attributes :

• id an integer that identifies the database (from 0 to N)
• name the database name (just for information, you can use any name)
• driver the JDBC driver class name
• url the JDBC URL to access the database

If you plan to generate code for JPA you can also define :

• typeName the type of database (eg "POSTGRESQL", "DERBY", "H2", "ORACLE", etc)
• dialect the JPA dialect (eg "org.hibernate.dialect.MySQLDialect")

Set the following JDBC properties ( in a <property> tag ) :

• property name user the database user
• property name password the database user's password
• if necessary you can define any other JDBC specific properties required by your database

Define the following information used to retrieve the JDBC METADATA ( in the <metadata> tag ):

• catalog the database catalog to be used if any ("" for void, "!" for null)
• schema the database schema containing the tables you want to use ("" for void, "!" for null)
• table-name-pattern the pattern to filter the tables names (eg "%" for all tables )
• table-types the type of tables to be used (eg "TABLE VIEW", "TABLE", "VIEW")
• table-name-exclude a pattern to exclude some tables (usually void)
• table-name-include a pattern to include some tables (usually void)

List the defined databases

To see all databases currently defined you can use the ldb command (List DB)

Provide the JDBC driver

Telosys needs a JDBC driver to be able to connect to the database.

So put the ".jar" file containing the JDBC driver class in the "lib" folder.

For example, for a "Derby" database put the "derbylient.jar" in "TelosysTools/lib".

Check the database connection

Once the database is defined in the databases.dbcfg file and its driver .jar file is available in the "lib" folder you can check the connection.

To check the connection use the cdb command (Check DB)

You can use cdb with or without the database id :

• cdb without argument will check the default database
• cdb 2 with argument "2" will check the database with id "2"

Generate your model

Once you have validated the connection to the database you are ready to generate the model.

To create a new "db model" use the ndbm command (New DB Model)

You can use ndbm with or without the database id :

• ndbm without argument will create a model from the default database
• ndbm 2 with argument "2" will create a model from the database with id "2"

Commands summary

• edb Edit DB
• ldb List DB
• cdb Check DB
• ndbm New DB Model

Use ? command-name to get help