molt-fetch

Migrate data from PostgreSQL, MySQL, Oracle, and MSSQL into CockroachDB.

18|8|Updated Feb 19, 2026

Search Tags:#postgresql #migration #mysql #data-migration #mssql #cockroachdb #molt

Ready to run

npx skills add https://github.com/cockroachlabs/cockroachdb-skills --skill molt-fetch

💬 Prompt for ChatGPT / Claude Chat▼

Please help me install this Agent Skill.
Skill: molt-fetch
Source: https://github.com/cockroachlabs/cockroachdb-skills/tree/main/skills/onboarding-and-migrations/molt-fetch
Command: npx skills add https://github.com/cockroachlabs/cockroachdb-skills --skill molt-fetch

SYSTEM DOCUMENTATION & REQUIREMENTS

💡 This Skill includes references (resource) components.

What problem does it solve?

Migrating data across database platforms is complex and error-prone; molt fetch provides a structured, repeatable workflow to move data from PostgreSQL, MySQL, Oracle, and MSSQL into CockroachDB using configurable storage and resume-friendly operations.

Core Features & Use Cases

Bulk data migration from multiple source databases into CockroachDB with configurable storage backends.
Supports resume/fault-tolerant workflows, various table-handling strategies (none, drop-on-target-and-recreate, truncate-if-exists), and verification steps.
Use Case: teams migrating legacy databases to CockroachDB with minimized downtime and clear rollback paths.

Quick Start

Run molt fetch with your source and target connections and a storage backend to begin a migration.

Frequently Asked Questions about molt-fetch

High-intent search queries and answers about installing and using this skill.

FAQPage Schema

How do I migrate data from PostgreSQL, MySQL, or MSSQL into CockroachDB?▼

You can migrate data into CockroachDB using molt fetch by configuring source and target database connections alongside a storage backend. It supports bulk data migration from PostgreSQL, MySQL, Oracle, and MSSQL with fault-tolerant workflows.

Can I resume a database migration to CockroachDB after a failure?▼

Yes, data migration to CockroachDB supports resume-friendly operations using resumption tokens. These tokens allow you to recover from failures across large datasets without restarting the entire transfer process.

What table handling strategies are available when migrating data to CockroachDB?▼

Data migration to CockroachDB supports multiple table-handling strategies, including none, drop-on-target-and-recreate, and truncate-if-exists. These options help manage existing schema conflicts during the transfer process.

Do I need special permissions to migrate data into CockroachDB?▼

Yes, migrating data into CockroachDB requires the molt binary and appropriate permissions to read from your source database and write to the target CockroachDB instance. Accessible source and target connections are mandatory.

What is the best way to handle large dataset migrations to CockroachDB?▼

The best way to handle large dataset migrations to CockroachDB is using configurable storage backends with resumption tokens. This structured approach minimizes downtime and provides clear rollback paths for legacy database transfers.

Does data migration to CockroachDB support verification steps after transfer?▼

Yes, data migration to CockroachDB includes verification steps to ensure data integrity after the transfer. This verification process confirms that your legacy database records accurately match the target CockroachDB instance.