# v0.5.0 — Row-Level Security, ETL Gating, and API Polish

> **Full technical details:** [v0.5.0.md-full.md](v0.5.0.md-full.md)

**Status: ✅ Released** | **Scope: Medium** (~3 weeks)

> Stream tables now respect PostgreSQL's row-level security policies,
> ETL pipelines can pause change capture while loading bulk data, and the
> API surface is cleaned up based on early user feedback.

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## What problem does this solve?

Enterprise deployments often enforce access controls at the row level —
different users see different rows depending on their role or tenant. Stream
tables need to respect these rules. ETL pipelines that bulk-load data need a
way to prevent half-loaded data from appearing in stream table results. And
after the v0.2–v0.4 feature sprint, the API had accumulated some rough edges
that needed polishing.

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## Row-Level Security (RLS) Support

PostgreSQL's **row-level security** (RLS) feature lets you define policies
such as "users can only see orders belonging to their own organisation." These
policies are enforced transparently by the database for regular queries.

Stream tables now fully respect RLS. When a stream table is refreshed, the
differential engine applies the same RLS policies as a direct query would.
The stream table result reflects only the rows the *owner* of the stream
table is allowed to see.

*In plain terms:* if your database uses row-level security for multi-tenant
isolation, your stream tables will correctly reflect only the data each
tenant should see.

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## Bootstrap Source Gating: Pause and Resume

ETL pipelines typically load data in large batches — they might insert
millions of rows over several minutes before the data is complete and
consistent. If pg_trickle's change capture is active during this load, it
may generate a stream table that reflects a half-loaded state.

**Bootstrap source gating** allows an ETL pipeline to call
`pgtrickle.pause_source(table_name)` before loading and
`pgtrickle.resume_source(table_name)` after, ensuring that change capture
only starts once the full batch is committed and consistent.

*In plain terms:* ETL pipelines can safely load large batches without
triggering intermediate stream table refreshes from incomplete data.

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## API Ergonomics

Based on feedback from early users, several API improvements were made:

- `create_stream_table` now validates the query immediately at creation time
  and returns a helpful error message if the query uses an unsupported pattern,
  rather than failing silently on the first refresh
- `drop_stream_table` is more robust — it cleans up change buffers, triggers,
  and catalog rows even if some were already missing (idempotent cleanup)
- Better parameter names and documentation in all SQL functions

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## Scope

v0.5.0 adds RLS support (necessary for multi-tenant deployments), ETL
gating (necessary for reliable bulk loading), and API polish that reduces
friction in day-to-day use. Together these make pg_trickle more production-
ready for enterprise environments.