migration_PG 12

docs/reference/postgresql12_migration.md

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+# Migrate from PostgreSQL 12
+
+!!! info "Important"
+    Percona Everest 1.6.0 has officially discontinued support for PostgreSQL 12. To ensure compatibility, security, and access to new features, it is highly recommended to migrate to PostgreSQL 13 or later.
+
+## Preparation before migration
+
+Before migrating from PostgreSQL 12, it's important to prepare thoroughly to ensure a smooth transition. Here are the key steps:
+{.power-number}
+
+1. **Backup your data** - Create a complete backup of your data before upgrading.
+
+2. **Check Compatibility** - Verify that your extensions and configurations are compatible with the new PostgreSQL version.
+
+3. **Install the new version** – Download and install the target PostgreSQL release.
+
+
+## Choose a migration option
+
+When upgrading from PostgreSQL 12, it is essential to choose a migration method that suits your environment. For a smooth transition, consider the following factors during migration:
+
+- Data size
+
+- Downtime tolerance
+
+- Infrastructure (Kubernetes, cloud, on-premise)
+
+PostgreSQL offers several migration options. Each method has its own benefits and trade-offs in terms of speed, complexity, and risk.
+
+Review PostgreSQL documentation to select the best option for your environment.
+
+💡 Need assistance? Connect with the Percona Everest community or consult a Percona Expert. connect with [Percona Everest community](https://forums.percona.com/t/welcome-to-perconas-community-forum/7){:target="_blank"}! Alternatively, you can always [Talk to a Percona Expert](../get-help.md#percona-experts).
+
+### Logical Dump and Restore vs. Logical Replication
+
+Two commonly used approaches to migrating a PostgreSQL database are Logical Dump and Restore and Logical Replication. Both methods help move data from one instance to another, but they have different purposes and distinct advantages.
+
+| **Feature**              | **Logical Dump and Restore**               | **Logical Replication**               |
+|--------------------------|-------------------------------------------|--------------------------------------|
+| **Setup complexity**      | Simple and portable                      | More complex, involves replication slots |
+| **Best suited for**           | One-time migrations, backups, and moving datasets across versions | Continuous data synchronization |
+| **Downtime Impact**      | Requires application downtime during migration | Minimal downtime |
+| **Primary Keys requirement** | No primary keys required; exports full table data regardless of constraints | Requires primary keys (or unique indexes) on tables|
+| **Schema compatibility**  | Allows schema modifications before restoration; supports cross-version migration | Requires schema compatibility between source and target databases |
+| **Performance**          | Can be slow for large datasets due to full export/import | More efficient for continuous updates, but may add replication overhead |
+
+### Logical Dump and Restore
+
+This option is recommended for **smaller databases** and **one-time migrations**.
+{.power-number}
+
+1. Use [pg_dump/pg_dumpall](https://www.postgresql.org/docs/current/app-pgdump.html) to **export** your data from PostgreSQL 12.
+
+2. Use [pg_restore](https://www.postgresql.org/docs/current/app-pgrestore.html) or [psql](https://www.postgresql.org/docs/current/app-psql.html) to import data into a new cluster.
+
+For comprehensive information, dive deep into the [PostgreSQL documentation on pg_dump](https://www.postgresql.org/docs/current/backup-dump.html).
+
+### Logical Replication
+
+This option is recommended for **minimal downtime**.
+
+Use [logical replication](https://www.postgresql.org/docs/current/logical-replication.html) to continuously replicate data from your PostgreSQL 12 cluster into a PostgresQLG 13+ cluster with little to no downtime.
+
+For comprehensive information, dive deep into the [PostgreSQL documentation on logical replication](https://www.postgresql.org/docs/current/logical-replication.html).
+
+
+
+
+
+
+

mkdocs-base.yml

@@ -217,6 +217,7 @@ nav:
   - Reference:
       - Breaking API changes: api_rbac.md
       - Limitations: reference/known_limitations.md
+      - Migrate from PostgreSQL 12: reference/postgresql12_migration.md
       - Telemetry on Percona Everest: reference/telemetry.md
       - Migrate to Percona Everest: reference/migration_guide.md
       - Copyright and licensing information: reference/copyright.md