Using Liquibase with Informix

IBM Informix is an embeddable relational database management system that specializes in online transaction processing and data warehouse workflows. For more information, see IBM Informix Servers Documentation.

Prerequisites

Install Liquibase.
Create a Liquibase project folder to store all Liquibase files.
Create a new Liquibase properties file or use the liquibase.properties file included in the installation package. For more information, see Specifying Properties in a Connection Profile.

Created an Informix database in the ANSI mode to enable implicit transactions by using the following statement:

CREATE DATABASE ansiDatabase WITH LOG MODE ANSI;

For more information, see CREATE DATABASE statement: Logging Options.

Install Drivers

To use Liquibase and Informix, you must download the JDBC driver JAR file.

Place your JAR file(s) in the liquibase/lib directory. For more information, see Adding and Updating Liquibase Drivers.

If you use Maven, you also need to download the driver JAR file and configure your Maven pom.xml file to use the local copy of the driver. For more information, see Configuring Liquibase Attributes in your Maven POM File. For example:

<dependency>
    <groupId>com.ibm.informix</groupId>
    <artifactId>jdbc</artifactId>
    <version>4.50.8</version>
</dependency>

Test Your Connection

For Liquibase and Informix to work, you need to:

Ensure your Informix database is configured. See Informix Installation for more information.
Specify the database URL in the Liquibase properties file:

url: jdbc:informix-sqli://localhost:9088/dbname:INFORMIXSERVER=dbserver

Create a text file called changelog (.xml, .sql, .json, or .yaml) in your project directory and add a changeset.

XML example

<?xml version="1.0" encoding="UTF-8"?>
<databaseChangeLog
	xmlns="http://www.liquibase.org/xml/ns/dbchangelog"
	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
	xmlns:ext="http://www.liquibase.org/xml/ns/dbchangelog-ext"
	xmlns:pro="http://www.liquibase.org/xml/ns/pro"
	xsi:schemaLocation="http://www.liquibase.org/xml/ns/dbchangelog
		http://www.liquibase.org/xml/ns/dbchangelog/dbchangelog-latest.xsd
		http://www.liquibase.org/xml/ns/dbchangelog-ext http://www.liquibase.org/xml/ns/dbchangelog/dbchangelog-ext.xsd
		http://www.liquibase.org/xml/ns/pro http://www.liquibase.org/xml/ns/pro/liquibase-pro-latest.xsd">
    <changeSet id="1" author="Liquibase">
    <createTable tableName="test_table">
           <column name="test_id" type="int">
                 <constraints primaryKey="true"/>
           </column>
           <column name="test_column" type="varchar"/>
    </createTable>
    </changeSet>
</databaseChangeLog>

SQL example

-- liquibase formatted sql

-- changeset liquibase:1
CREATE TABLE test_table (test_id INT, test_column VARCHAR, PRIMARY KEY (test_id))

Tip: Formatted SQL changelogs generated from Liquibase versions before 4.2 might cause issues because of the lack of space after a double dash ( -- ). To fix this, add a space after the double dash. For example: -- liquibase formatted sql instead of --liquibase formatted sql and -- changeset myname:create-table instead of --changeset myname:create-table

YAML example

databaseChangeLog:
   - changeSet:
       id: 1
       author: Liquibase
       changes:
       - createTable:
           columns:
           - column:
               name: test_column
               type: INT
               constraints:  
                   primaryKey:  true  
                   nullable:  false  
                   tableName: test_table

JSON example

{ 
  "databaseChangeLog": [
  {
	"changeSet": {
	  "id": "1",
      "author": "Liquibase",
	  "changes": [
	    {
		  "createTable": {
		    "columns": [
			{
			  "column": 
		      {
				"name": "test_column",
				"type": "INT",
				"constraints": 
			  {
				"primaryKey": true,
				"nullable": false
				}
				}
			  }]
			,
			"tableName": "test_table"
		  }
		}]
	  }
	}]
  }

Navigate to your project folder in the CLI and run the Liquibase status command to see whether the connection is successful. You can pass arguments in the CLI or keep them in the Liquibase properties file.

liquibase --username=test --password=test --changelog-file=<changelog.xml> status

Inspect the SQL with the update-sql command. Then make changes to your database with the update command.

liquibase --changelog-file=<changelog.xml> update-sql
liquibase --changelog-file=<changelog.xml> update

From a database UI tool, ensure that your database contains the table you added along with the DATABASECHANGELOG table and DATABASECHANGELOGLOCK table.

If you add a changeset with the procedure but receive an error message during the runtime, add the splitStatements attribute set to false to your changeset as follows:

--changeset bob:5 splitStatements:false
CREATE PROCEDURE raise_prices ( per_cent INT)
        UPDATE stock SET unit_price = unit_price + (unit_price * (per_cent/100) );
END PROCEDURE;