# Features

Altertable catalog tables support capabilities that shape how data is written, queried, and maintained over time. Use these features when you need predictable scan performance, historical reads, reusable logic, or incremental downstream processing.

Partitioning and sorted tables improve write layout and query pruning. Time travel and views help you inspect history and encapsulate logic. Data change feeds, macros, and optimize-table support operational pipelines and housekeeping.

- [Partitioning](/docs/lakehouse/features/partitioning.md): Partition Altertable catalog tables by column or transform to improve write layout and query pruning.
- [Sorted tables](/docs/lakehouse/features/sorted-tables.md): Configure a physical sort order on Altertable catalog tables to improve min/max statistics and query pruning.
- [Transactions](/docs/lakehouse/features/transactions.md): Run ACID transactions against Altertable catalogs with snapshot isolation and all-or-nothing semantics.
- [Time travel](/docs/lakehouse/features/time-travel.md): Query Altertable catalog tables as of earlier snapshots using version or timestamp bounds for audits and reproducible reports.
- [Views](/docs/lakehouse/features/views.md): Create, store, and query SQL views in Altertable catalog metadata so teams can reuse governed lakehouse logic.
- [Macros](/docs/lakehouse/features/macros.md): Define reusable scalar and table macros in Altertable catalog metadata with standard CREATE MACRO syntax.
- [Data change feed](/docs/lakehouse/features/data-change-feed.md): Query inserts, updates, and deletes between catalog snapshots using table\_changes and related functions.
- [Full-text search](/docs/lakehouse/features/full-text-search.md): Search text across Altertable tables with SQL-native full-text search for faster discovery across lakehouse data.
- [Optimize table](/docs/lakehouse/features/optimize-table.md): Optimize Altertable tables for better storage layout, faster queries, and improved lakehouse performance at scale.
- [MATCH\_RECOGNIZE](/docs/lakehouse/features/match-recognize.md): Find ordered row patterns such as funnels, journeys, and state transitions with SQL:2016-style MATCH\_RECOGNIZE.
- [SESSIONIZE](/docs/lakehouse/features/sessionize.md): Assign ordered events to gap-based sessions and calculate session-level measures with DuckDB SQL in Altertable.
- [JOURNEYS](/docs/lakehouse/features/journeys.md): Discover observed paths from a start event to an end event, including drop-offs, with the JOURNEYS operator in Altertable.