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.

Supported versions

• 12.10.X

Prerequisites

• Install Liquibase.
• Create a Liquibase project folder to store all Liquibase files. You can do this manually or with the init project command.
• Create a new Liquibase properties file or use the liquibase.properties file included in the installation package. For more information, see Create and Configure a liquibase.properties File.

Install drivers

To use Liquibase and Informix, you need the JDBC driver JAR file (Maven download).

Place your JAR file(s) in the liquibase/lib directory. Read more: Adding and Updating Liquibase Drivers.

If you use Maven, you must include the driver JAR as a dependency in your pom.xml file. Read more: Configuring Liquibase Attributes in your Maven POM File.

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

Test your connection

1. Ensure your Informix database is configured. Create 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 Informix Installation and CREATE DATABASE statement: Logging Options.

2. Specify the database URL in the Liquibase properties file. Liquibase does not parse the URL. You can either specify the full database connection string or specify the URL using your database's standard JDBC format:

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

Tip: To apply a Liquibase Pro key to your project, add the following property to the Liquibase properties file: licenseKey: <paste code here>

3. 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(256), 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"
		  }
		}]
	  }
	}]
  }

4. Navigate to your project folder in the CLI and run the Liquibase status command to see whether the connection is successful:

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

Note: You can pass arguments in the CLI or keep them in the Liquibase properties file.

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

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

6. From a database UI tool, ensure that your database contains the test_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;