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Migration playbook: MySQL / MariaDB → PostgreSQL

MySQL to PostgreSQL migration and schema translation

Move MySQL databases to PostgreSQL for transactional DDL, richer indexing, JSONB and extensions such as PostGIS and pgvector, with live replication until cutover.

Migration drivers

Why teams make this move

Driver 01

Transactional schema changes

MySQL commits DDL implicitly, so a failed migration can leave a schema half-changed; PostgreSQL runs DDL inside transactions.

Driver 02

Query and JSON capabilities

Partial and expression indexes, JSONB with GIN indexes, and a mature planner for complex queries.

Driver 03

Extensions

PostGIS for geospatial data and pgvector for embeddings, inside the same database.

Execution sequence

How the migration runs

Each phase ends with a check you can verify — data parity, error rates, latency — and the rollback path is agreed before any traffic moves.

  1. 01Phase

    Schema translation and audit

    Converting MySQL types (TINYINT(1), DATETIME, ENUM, unsigned integers) to PostgreSQL equivalents with pgloader and a manual review.

  2. 02Phase

    Change data capture

    Streaming live MySQL changes to PostgreSQL with Debezium and Kafka after the bulk load.

  3. 03Phase

    Shadow read verification

    Mirroring application reads to PostgreSQL to compare results and query plans.

  4. 04Phase

    Write cutover

    Pausing writes briefly, confirming replication has caught up, and switching connection strings.

Risk prevention

Pitfalls that derail this migration

Risk 01

Case-sensitivity mismatches

MySQL's case-insensitive collations hiding duplicates that PostgreSQL's unique constraints then reject.

Risk 02

Sequences out of sync

Forgetting to reset PostgreSQL sequences after bulk loading, which causes primary key collisions.

Risk 03

Implicit type coercion

MySQL leniently accepting invalid values (zero dates, empty strings as 0) that PostgreSQL rejects.

Before and after

What we measure

We take a baseline before any change and report the same numbers after cutover, from your own tools. They are the evidence of whether the migration worked — not figures promised in advance.

Row parity
Row counts and checksums per table before cutover
Query latency
Top queries by total time, compared on both databases
Write freeze
Measured in rehearsal, then at the real cutover

Questions

Frequently asked migration questions

Yes. We bulk-load historical data while change data capture streams new writes, so the final cutover is a short write freeze. We rehearse it first, so you know the real number for your data before the day.

They are rewritten as PL/pgSQL functions and triggers, reviewed for behavior differences (transactions, error handling, type coercion) and covered by tests before cutover.

Rehearse the cutover before the real one

Tell us about your data volume, traffic and timeline. An engineer will reply within one business day to set up a call about the migration plan and its rollback path.