Create a Test Database.md

Creating a test database.

This document describes how to create a test database to test changes before running them on the wecc database. There are many ways to do this however we will be creating a wecc-test database. If wecc-test already exists, you may already have a database you can use to test. It may however be out of sync with the wecc database.

We will be using Liquibase to make a copy of our database schema. Liquibase is a tool to manage database version however here we're only using it to copy over a database.

Prequisites

1. Install Liquibase.

2. Ensure you can access the wecc database.

3. Download the PostgreSQL JDBC driver.

Creating the test database

1. Create a database called wecc-test (e.g. using PGAdmin).

2. Create a schema called switch in the wecc-test database.

3. On your computer where you've installed liquibase create a folder where you'll work out of.

4. Create a file called liquibase.properties with the following content.

changeLogFile:dbchangelog.sql
url:  jdbc:postgresql://localhost:5432/wecc
username:  postgres  
password:  password
classpath:  postgresql-42.2.21.jar
defaultSchemaName: switch

classpath should point to the driver you downloaded. Replace username and password with your database username and password. Ensure that the database is running and accessible at the provided url.

5. Run liquibase generateChangeLog. This will create dbchangelog.sql containing all the SQL commands needed to recreate the database on wecc-test.

6. Modify liquibase.properties to point to the wecc-test database (change the url to wecc-test).

7. Run liquibase update to run the SQL changes on the wecc-test database. This might take a long time to run.

8. Delete the liquibase.properties file so that your password is no longer stored in plain text.

Note: Liquibase will also create a databasechangelog and databasechangeloglock table which can be ignored.