Initial Sync and Indexing

After configuring logical replication, follow these steps to prepare your replica for queries.

Operating Model

When ParadeDB is used as a logical subscriber:

Your application writes to tables on the publisher
Postgres logical replication applies those row changes to matching tables on ParadeDB
ParadeDB maintains ParadeDB indexes locally on the subscriber
Search and analytics queries run against ParadeDB instead of the primary

This keeps the source database authoritative while isolating search traffic from OLTP traffic.

Logical replication copies row changes into ParadeDB, but it does not copy ParadeDB indexes from the publisher. For the deployment described in this guide, build the ParadeDB indexes directly on the ParadeDB subscriber.

1. Wait for the Initial Copy to Finish

By default, logical replication starts with an initial copy of the existing data. Let Postgres finish copying the base table data before you build ParadeDB indexes. This avoids extra indexing work during the bootstrap phase.

Initial-Copy Parallelism

max_sync_workers_per_subscription controls how many tables a subscription can copy at once when it is created or refreshed. The default is 2. Raising it lets multi-table subscriptions copy more tables at once, but requires more slots and workers. See Replication Configuration for capacity settings.

Checking Copy Progress

On ParadeDB, you can check whether the initial copy is still running with:

SELECT
  subname,
  worker_type,
  CASE WHEN relid = 0 THEN NULL ELSE relid::regclass END AS table_name,
  latest_end_time
FROM pg_stat_subscription
ORDER BY 1, 2, 3;

The initial copy is complete when there are no remaining rows with worker_type = 'table synchronization'. If you want a stricter per-table check, run:

SELECT srrelid::regclass AS table_name, srsubstate
FROM pg_subscription_rel
ORDER BY 1;

The initial copy is complete when every replicated table is in state r (ready).

2. Build ParadeDB Indexes

Once the replicated tables are caught up, create ParadeDB indexes locally on the ParadeDB logical replica:

CREATE INDEX mock_items_search_idx ON public.mock_items
USING paradedb (id, description, category, rating)
WITH (key_field='id');

After this, ongoing replicated INSERT, UPDATE, and DELETE operations will keep the ParadeDB index current automatically.

3. Query ParadeDB

Your application can now issue queries to ParadeDB without adding indexes to the primary database:

SELECT description, pdb.score(id)
FROM mock_items
WHERE description ||| 'running shoes' AND rating > 2
ORDER BY score DESC
LIMIT 5;

For more query examples, see Run Your First Queries.

Deployment

Replication

Index Maintenance

Performance

Administration

Continuous Integration

Initial Sync and Indexing

Operating Model

1. Wait for the Initial Copy to Finish

Initial-Copy Parallelism

Checking Copy Progress

2. Build ParadeDB Indexes

3. Query ParadeDB

​Operating Model

​1. Wait for the Initial Copy to Finish

​Initial-Copy Parallelism

​Checking Copy Progress

​2. Build ParadeDB Indexes

​3. Query ParadeDB

Operating Model

1. Wait for the Initial Copy to Finish

Initial-Copy Parallelism

Checking Copy Progress

2. Build ParadeDB Indexes

3. Query ParadeDB