Databricks Labs Remorph

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Table of Contents

• Introduction
  • Remorph
  • Transpile
  • Reconcile
• Environment Setup
• How to use Transpile
  • Installation
  • Verify Installation
  • Execution Pre-Set Up
  • Execution
• How to use Reconcile
  • Installation
  • Verify Installation
  • Execution Pre-Set Up
  • Execution
• Frequently Asked Questions
  • Transpile
  • Reconcile
• Common Error Codes
• Project Support

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Introduction

Remorph

Remorph stands as a comprehensive toolkit meticulously crafted to facilitate seamless migrations to Databricks. This suite of tools is dedicated to simplifying and optimizing the entire migration process, offering two distinctive functionalities – Transpile and Reconcile. Whether you are navigating code translation or resolving potential conflicts, Remorph ensures a smooth journey for any migration project. With Remorph as your trusted ally, the migration experience becomes not only efficient but also well-managed, setting the stage for a successful transition to the Databricks platform.

Transpile

Transpile is a self-contained SQL parser, transpiler, and validator designed to interpret a diverse range of SQL inputs and generate syntactically and semantically correct SQL in the Databricks SQL dialect. This tool serves as an automated solution, named Transpile, specifically crafted for migrating and translating SQL scripts from various sources to the Databricks SQL format. Currently, it exclusively supports Snowflake as a source platform, leveraging the open-source SQLglot.

Transpile stands out as a comprehensive and versatile SQL transpiler, boasting a robust test suite to ensure reliability. Developed entirely in Python, it not only demonstrates high performance but also highlights syntax errors and provides warnings or raises alerts for dialect incompatibilities based on configurations.

Transpiler Design Flow:

flowchart TD
    A(Transpile CLI) --> |Directory| B[Transpile All Files In Directory];
    A --> |File| C[Transpile Single File] ;
    B --> D[List Files];
    C --> E("Sqlglot(transpile)");
    D --> E
    E --> |Parse Error| F(Failed Queries)
    E --> G{Skip Validations}
    G --> |Yes| H(Save Output)
    G --> |No| I{Validate}
    I --> |Success| H
    I --> |Fail| J(Flag, Capture)
    J --> H

Reconcile

Reconcile is an automated tool designed to streamline the reconciliation process between source data and target data residing on Databricks. Currently, the platform exclusively offers support for Snowflake, Oracle and other Databricks tables as the primary data source. This tool empowers users to efficiently identify discrepancies and variations in data when comparing the source with the Databricks target.

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Environment Setup

1. Databricks CLI - Ensure that you have the Databricks Command-Line Interface (CLI) installed on your machine. Refer to the installation instructions provided for Linux, MacOS, and Windows, available here.

2. Databricks Connect - Set up the Databricks workspace configuration file by following the instructions provided here. Note that Databricks labs use 'DEFAULT' as the default profile for establishing connections to Databricks.

3. Python - Verify that your machine has Python version 3.10 or later installed to meet the required dependencies for seamless operation.

   • Windows - Install python from here. Your Windows computer will need a shell environment (GitBash or WSL)
   • MacOS/Unix - Use brew to install python in macOS/Unix machines

Installing Databricks CLI on macOS

Install Databricks CLI via curl on Windows

Check Python version on Windows, macOS, and Unix

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How to Use Transpile

Installation

Upon completing the environment setup, install Remorph by executing the following command:

databricks labs install remorph

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Verify Installation

Verify the successful installation by executing the provided command; confirmation of a successful installation is indicated when the displayed output aligns with the example screenshot provided:

 databricks labs remorph transpile --help

Execution Pre-Set Up

1. Transpile necessitates input in the form of either a directory containing SQL files or a single SQL file.
2. The SQL file should encompass scripts intended for migration to Databricks SQL.

Below is the detailed explanation on the arguments required for Transpile.

• input-sql [Required] - The path to the SQL file or directory containing SQL files to be transpiled.
• source [Required] - The source platform of the SQL scripts. Currently, only Snowflake is supported.
• output-folder [Optional] - The path to the output folder where the transpiled SQL files will be stored. If not specified, the transpiled SQL files will be stored in the same directory as the input SQL file.
• skip-validation [Optional] - The default value is True. If set to False, the transpiler will validate the transpiled SQL scripts against the Databricks catalog and schema provided by user.
• catalog-name [Optional] - The name of the catalog in Databricks. If not specified, the default catalog transpiler_test will be used.
• schema-name [Optional] - The name of the schema in Databricks. If not specified, the default schema convertor_test will be used.

Execution

Execute the below command to intialize the transpile process.

 databricks labs remorph transpile --input-sql <absolute-path> --source <snowflake> --output-folder <absolute-path> --skip-validation <True|False> --catalog-name <catalog name> --schema-name <schema name>

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How to Use Reconcile

Installation

Install Reconciliation with databricks labs cli.

databricks labs install remorph

Verify Installation

Verify the successful installation by executing the provided command; confirmation of a successful installation is indicated when the displayed output aligns with the example screenshot provided:

 databricks labs remorph reconcile --help

Execution Pre-Set Up

Please refer to the Reconcile Configuration Guide for detailed instructions on how to set up the configuration.

Execution

Execute the below command to initialize the reconcile process.

 databricks labs remorph reconcile

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Frequently Asked Questions

Transpiler

TBD

Reconciler

Can we reconcile for Databricks without UC as a target?

The reconciliation target is always Databricks with UC enabled. Reconciler supports non-uc Databricks only as a source.

What would happen if my dataset had duplicate records?

Duplicates are not handled in the reconciler. If run with duplicates, it would result in inconsistent output. We can implement some workarounds to handle the duplicates, and the solution varies from dataset to dataset.

Are User Transformations applicable for Schema Validations?

No. User Transformations are not applied for Schema Validation.Only select_columns,drop_columns and column_mapping is valid for schema validation.

Can we apply Aggregate or multi-column transformations as user transformations?

No. Aggregate transformations or multi-column transformations are not supported.

Does Reconciler support all complex data types?

Not all complex data types are supported currently.Reconciler do support UDFs for complex datatypes.Please refer here for examples.

Does Reconciler support `Threshold Validation` for report type as `row`?

No. Threshold Validation is supported only for reports with the report type data or all, generally tables with primary keys.

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Common Error Codes:

TBD

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Project Support

Please note that all projects in the /databrickslabs github account are provided for your exploration only, and are not formally supported by Databricks with Service Level Agreements (SLAs). They are provided AS-IS and we do not make any guarantees of any kind. Please do not submit a support ticket relating to any issues arising from the use of these projects.

Any issues discovered through the use of this project should be filed as GitHub Issues on the Repo. They will be reviewed as time permits, but there are no formal SLAs for support.