Data migration and synchronization methods between versant object database and relational database

Versant Object DataASE (Versant) is an object -oriented database management system that is widely used in many applications.In some cases, data need to be migrated from Versant to relational databases or synchronization with relational databases.This article will introduce some methods of data migration and synchronization Versant and relational databases, and provide necessary programming code and related configuration. 1. Data migration method 1. Use ETL tools: ETL (EXTRACT, Transform, LOAD) tools can help extract data from Versant and convert it into formats that can be stored in relational databases.Common ETL tools include Oracle Data Integrator, Informatica PowerCenter, etc.The following is a sample code for data migration using Oracle Data Integrator: import oracle.odi.core.persistence.transaction.support.DefaultTransactionDefinition; import oracle.odi.core.persistence.transaction.support.TransactedResourceImpl; import oracle.odi.domain.model.OdiModel; import oracle.odi.domain.topology.OdiPhysicalSchema; import oracle.odi.domain.topology.OdiTechnology; import oracle.odi.domain.topology.finder.IOdiPhysicalSchemaFinder; import oracle.odi.generation.ODISchema; import oracle.odi.generation.support.ODISchemaImpl; import oracle.odi.runtime.agent.Agent; import oracle.odi.runtime.agent.InvocationException; import oracle.odi.runtime.agent.invocation.StartupParams; import oracle.odi.runtime.agent.invocation.loadplan.OdiLoadPlan; import oracle.odi.runtime.agent.invocation.loadplan.OdiLoadPlanInstance; import oracle.odi.runtime.loadplan.OdiLoadPlanExecutor; import oracle.odi.runtime.loadplan.OdiLoadPlanExecutorFactory; public class VersantToRelationalETL { public static void main(String[] args) { String versantConnectionString = "jdbc:versant://localhost:50000/database"; String relationalConnectionString = "jdbc:oracle:thin:@localhost:1521:database"; String versantUsername = "versant_user"; String versantPassword = "versant_password"; String relationalUsername = "relational_user"; String relationalPassword = "relational_password"; String etlLoadPlan = "VersantToRelational_ETL_LoadPlan"; try { // Connect to Versant database ODISchema versantSchema = new ODISchemaImpl(versantConnectionString, versantUsername, versantPassword); // Connect to Relational database ODISchema relationalSchema = new ODISchemaImpl(relationalConnectionString, relationalUsername, relationalPassword); // Get the ETL load plan OdiLoadPlan loadPlan = new OdiLoadPlan(versantSchema, etlLoadPlan); // Create/load data OdiLoadPlanExecutorFactory executorFactory = OdiLoadPlanExecutor.getExecutorFactory(Agent.LOAD_PLAN_EXECUTION_AGENT); OdiLoadPlanExecutor executor = executorFactory.getLoadPlanExecutor(); OdiLoadPlanInstance planInstance = executor.startLoadPlanInstance(loadPlan); // Close connections versantSchema.close(); relationalSchema.close(); } catch (InvocationException e) { e.printStackTrace(); } } } 2. Use custom code: If you do not use the ETL tool budget, you can also use custom code to achieve data migration.The following is an example code written in Java: import com.versant.jpa.RestoreConfig; import com.versant.jpa.Restorer; import com.versant.trans.TransSession; import com.versant.trans.VQLSession; public class VersantToRelationalMigration { public static void main(String[] args) { String versantConnectionString = "jdbc:versant://localhost:50000/database"; String relationalConnectionString = "jdbc:mysql://localhost:3306/database"; String versantUsername = "versant_user"; String versantPassword = "versant_password"; String relationalUsername = "relational_user"; String relationalPassword = "relational_password"; TransSession transSession = new TransSession(versantConnectionString, versantUsername, versantPassword); VQLSession vqlSession = transSession.newVQLSession(); // Retrieve objects from Versant database String vqlQuery = "select * from com.example.Entity"; Object[] objects = vqlSession.retrieve(vqlQuery); // Store objects in Relational database RestoreConfig restoreConfig = new RestoreConfig(relationalConnectionString, relationalUsername, relationalPassword); Restorer restorer = new Restorer(restoreConfig); for (Object object : objects) { restorer.store(object); } // Close connections vqlSession.close(); transSession.close(); } } 2. Data synchronization method For real -time simultaneous synchronization of data between VERSANT and relational databases, the following methods can be used: 1. Use a trigger: Set the trigger in the Versant database so that the data changes are sent to the relational database when the data changes.The following is an example code written by Trigger API provided by Versant: import com.versant.odbms.VDatabase; import com.versant.odbms.VOD; public class VersantToRelationalSync { public static void main(String[] args) { String versantConnectionString = "jdbc:versant://localhost:50000/database"; String relationalConnectionString = "jdbc:mysql://localhost:3306/database"; String versantUsername = "versant_user"; String versantPassword = "versant_password"; String relationalUsername = "relational_user"; String relationalPassword = "relational_password"; // Connect to Versant database VDatabase versantDatabase = VOD.openDatabase(versantConnectionString, versantUsername, versantPassword); // Connect to Relational database Connection relationalConnection = DriverManager.getConnection(relationalConnectionString, relationalUsername, relationalPassword); // Create a Versant trigger to capture data changes String triggerScript = "CREATE TRIGGER versant_trigger ON com.example.Entity AFTER [INSERT, UPDATE, DELETE] AS BEGIN " + "INSERT INTO relational_table (column1, column2, column3) VALUES (?, ?, ?) " + "END"; Statement relationalStatement = relationalConnection.createStatement(); relationalStatement.execute(triggerScript); // Close connections versantDatabase.close(); relationalConnection.close(); } } 2. Use message queue: By setting a message queue between the Versant database and the relationship database, you can change the change notification to the relational database through message transmission when the data is changed.The following is a sample code for data synchronization using the Java message queue (such as Apache Kafka): import org.apache.kafka.clients.producer.KafkaProducer; import org.apache.kafka.clients.producer.ProducerRecord; public class VersantToRelationalSync { public static void main(String[] args) { String versantConnectionString = "jdbc:versant://localhost:50000/database"; String relationalConnectionString = "localhost:9092"; String versantUsername = "versant_user"; String versantPassword = "versant_password"; String relationalTopic = "relational_topic"; // Connect to Versant database // Retrieve objects from Versant database ... // Connect to Relational database Properties props = new Properties(); props.put("bootstrap.servers", relationalConnectionString); props.put("key.serializer", "org.apache.kafka.common.serialization.StringSerializer"); props.put("value.serializer", "org.apache.kafka.common.serialization.StringSerializer"); KafkaProducer<String, String> producer = new KafkaProducer<>(props); // Send data changes to Kafka topic for (Object object : objects) { String data = convertObjectToJson(object); // Convert object to JSON format producer.send(new ProducerRecord<>(relationalTopic, data)); } // Close connections producer.close(); ... } } Summarize: This article introduces the method of migrating data from Versant Object DataBase to relational databases and data synchronization.For data migration, you can use ETL tools or custom code to implement; for data synchronization, you can use the trigger or message queue to pass the change in real time.It is hoped that these examples and related configurations can help readers realize data migration and synchronization between VERSANT and relational databases.