knowledge_base: add lakebase_synced_tables example

knowledge_base/lakebase_synced_tables/.gitignore

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+.databricks

knowledge_base/lakebase_synced_tables/README.md

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+# Lakebase synced tables
+
+This Declarative Automation Bundles example syncs a Unity Catalog Delta table to Lakebase Postgres. Each target creates its own project, branch, endpoint, and synced table.
+
+See the [Lakebase Autoscaling documentation](https://docs.databricks.com/aws/en/oltp/) for more information.
+
+## Prerequisites
+
+- Databricks CLI v1.20.0 or above.
+- A workspace with Lakebase Autoscaling and serverless pipelines.
+- A source Delta table with change data feed enabled and an `id` primary key column.
+- A standard catalog and schema for pipeline storage.
+- A new project ID. The bundle creates and purges its project during deployment and cleanup.
+- The `psql` client, for the row count in step 5.
+
+## Usage
+
+1. Set a unique project ID and your Unity Catalog object names.
+
+   ```sh
+   export BUNDLE_VAR_project_id=my-synced-tables
+   export BUNDLE_VAR_source_table=main.example.source_table
+   export BUNDLE_VAR_destination_table=main.example.synced_source_table
+   export BUNDLE_VAR_pipeline_storage_catalog=main
+   export BUNDLE_VAR_pipeline_storage_schema=example
+   ```
+
+2. Validate the bundle.
+
+   ```sh
+   databricks bundle validate
+   ```
+
+3. Deploy the development project and synced table.
+
+   ```sh
+   databricks bundle deploy
+   ```
+
+4. Deploy the production project and synced table.
+
+   ```sh
+   databricks bundle deploy -t prod
+   ```
+
+5. Verify the development and production sync status.
+
+   ```sh
+   databricks postgres get-synced-table "synced_tables/${BUNDLE_VAR_destination_table}_dev"
+   databricks postgres get-synced-table "synced_tables/${BUNDLE_VAR_destination_table}_prod"
+   databricks psql --project "${BUNDLE_VAR_project_id}-dev" --branch production --endpoint primary -- -d databricks_postgres -c "SELECT count(*) FROM ${BUNDLE_VAR_destination_table#*.}_dev;"
+   ```
+
+6. Remove the resources for each deployed target.
+
+   ```sh
+   databricks bundle destroy --auto-approve
+   databricks bundle destroy -t prod --auto-approve
+   ```

knowledge_base/lakebase_synced_tables/databricks.yml

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+bundle:
+  name: lakebase-synced-tables
+  databricks_cli_version: ">= 1.20.0"
+
+include:
+  - resources/*.yml
+
+variables:
+  project_id:
+    description: Unique Lakebase project ID
+  source_table:
+    description: Three-part name of the source Delta table
+  destination_table:
+    description: Three-part name of the destination synced table
+  pipeline_storage_catalog:
+    description: Standard catalog for pipeline storage
+  pipeline_storage_schema:
+    description: Schema for pipeline storage
+targets:
+  dev:
+    default: true
+    mode: development
+    workspace:
+      root_path: /Workspace/bundle-examples/${bundle.name}/${bundle.target}/${workspace.current_user.short_name}
+  prod:
+    mode: production
+    workspace:
+      root_path: /Workspace/bundle-examples/${bundle.name}/${bundle.target}

knowledge_base/lakebase_synced_tables/resources/lakebase.postgres.yml

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+resources:
+  postgres_projects:
+    synced_tables:
+      project_id: ${var.project_id}-${bundle.target}
+      display_name: Lakebase synced tables example
+      pg_version: 17
+      purge_on_delete: true
+
+  postgres_branches:
+    target_branch:
+      parent: ${resources.postgres_projects.synced_tables.id}
+      branch_id: production
+      no_expiry: true
+      replace_existing: true
+      purge_on_delete: true
+
+  postgres_endpoints:
+    target_endpoint:
+      parent: ${resources.postgres_branches.target_branch.id}
+      endpoint_id: primary
+      endpoint_type: ENDPOINT_TYPE_READ_WRITE
+      replace_existing: true
+      autoscaling_limit_min_cu: 0.5
+      autoscaling_limit_max_cu: 1
+      suspend_timeout_duration: 60s
+
+  postgres_snapshot_schedules:
+    daily_snapshots:
+      branch: ${resources.postgres_branches.target_branch.id}
+      schedule:
+        - daily_schedule:
+            hour: 0
+          retention: 3600s
+
+  postgres_synced_tables:
+    example:
+      synced_table_id: ${var.destination_table}_${bundle.target}
+      source_table_full_name: ${var.source_table}
+      branch: ${resources.postgres_branches.target_branch.id}
+      postgres_database: databricks_postgres
+      primary_key_columns:
+        - id
+      scheduling_policy: TRIGGERED
+      new_pipeline_spec:
+        storage_catalog: ${var.pipeline_storage_catalog}
+        storage_schema: ${var.pipeline_storage_schema}