Replicate Azure Data Lake Storage Data to Multiple Databases via the CData Sync CLI

Always-on applications rely on automatic failover capabilities and real-time access to data. CData Sync for Azure Data Lake Storage integrates live Azure Data Lake Storage data into your mirrored databases, always-on cloud databases, and other databases such as your reporting server: Automatically synchronize with remote Azure Data Lake Storage data from Windows or any machine running Java.

You can use Sync's command-line interface (CLI) to easily control almost all aspects of the replication. You can use the CLI to replicate Azure Data Lake Storage data to one or many databases without any need to change your configuration.

Connect to Azure Data Lake Storage Data

You can save connection strings and other settings like email notifications in XML configuration files.

The following example shows how to replicate to SQLite.

Windows

<?xml version="1.0" encoding="UTF-8" ?>
<CDataSync><DatabaseType>SQLite</DatabaseType>
  <DatabaseProvider>System.Data.SQLite</DatabaseProvider>
  <ConnectionString>AuthScheme=AccessKey;AzureStorageAccount=myAccount;AzureAccessKey=myAccessKey;</ConnectionString>
  <ReplicateAll>False</ReplicateAll>
  <NotificationUserName></NotificationUserName>
  <DatabaseConnectionString>Data Source=C:\my.db</DatabaseConnectionString>
  <TaskSchedulerStartTime>09:51</TaskSchedulerStartTime>
  <TaskSchedulerInterval>Never</TaskSchedulerInterval>
</CDataSync>

Java

<?xml version="1.0" encoding="UTF-8" ?>
<CDataSync><DatabaseType>SQLite</DatabaseType><DatabaseProvider>org.sqlite.JDBC</DatabaseProvider>
<ConnectionString>AuthScheme=AccessKey;AzureStorageAccount=myAccount;AzureAccessKey=myAccessKey;</ConnectionString>
<ReplicateAll>False</ReplicateAll>
<NotificationUserName></NotificationUserName>
<DatabaseConnectionString>Data Source=C:\my.db</DatabaseConnectionString>
</CDataSync>

To connect with Azure Data Lake Storage, set the following connection properties:

• Connection Name: Enter a connection name of your choice.
• File Format: Select the file format you want to use. Sync supports CSV, PARQUET, and AVRO file formats.
• Azure Storage Account: Enter the name of your Azure storage account.
• URI: Enter the path of the file system and folder that contains your files (for example, adl://MyFileSystem/MyFolder).

CData Sync supports several authentication methods, including Azure Active Directory, Azure Managed Service Identity, Azure Service Principal, Service Principal Certificate, Azure Access Key, and Shared Access Signature.

Azure Access Key

To connect with an Azure access key, set the following properties:

• Auth Scheme: Select Access Key.
• Azure Access Key: Enter the access key associated with your storage account. Find it in the Azure portal under your storage account's Settings > Access keys.

For other authentication methods, refer to the Help documentation.

Configure Replication Queries

Sync enables you to control replication with standard SQL. The REPLICATE statement is a high-level command that caches and maintains a table in your database. You can define any SELECT query supported by the Azure Data Lake Storage API. The statement below caches and incrementally updates a table of Azure Data Lake Storage data:

REPLICATE MyFolder;

You can specify a file containing the replication queries. This enables you to use the same replication queries to replicate to several databases.

Run Sync

After you have configured the connection strings and replication queries, you can run Sync with the following command-line options:

Windows

ADLSSync.exe -g MySQLiteConfig.xml -f ADLSSync.sql

Java

java -Xbootclasspath/p:c:\sqlitejdbc.jar -jar ADLSSync.jar -g MySQLiteConfig.xml -f ADLSSync.sql