# Moose / Olap / Model View Documentation – Python

## Included Files
1. moose/olap/model-view/model-view.mdx

## Modeling Views

Source: moose/olap/model-view/model-view.mdx

Define standard ClickHouse Views for read-time projections

# Modeling Views

## Overview
Views are read-time projections in ClickHouse. A static `SELECT` defines the view over one or more base tables or other views. Moose wraps [ClickHouse `VIEW`](https://clickhouse.com/docs/en/sql-reference/statements/create/view) with a simple `View` class in Python. You provide the view name, the `SELECT`, and the list of source tables/views so Moose can order DDL correctly during migrations.

Use `View` when you want a virtual read-time projection and don’t need write-time transformation or a separate storage table. For write-time pipelines and backfills, use a Materialized View instead.

## Basic Usage

```python filename="BasicUsage.py" copy
from moose_lib import View
from tables import users, events

active_user_events = View(
    "active_user_events",
    """
    SELECT
      {events.columns.id}    AS event_id,
      {users.columns.id}     AS user_id,
      {users.columns.name}   AS user_name,
      {events.columns.ts}    AS ts
    FROM {events}
    JOIN {users} ON {events.columns.user_id} = {users.columns.id}
    WHERE {users.columns.active} = 1
    """,
    [events, users],
)
```

## Quick Reference

```python filename="Signature.py" copy
# View(name: str, select_statement: str, base_tables: list[OlapTable | View])
View(
    "view_name",
    "SELECT ... FROM {someTable}",
    [someTable],
)
```

The `SELECT` should be static (no runtime parameters). In TypeScript, prefer Moose’s `sql` template for safe table/column interpolation; in Python, use string templates with `{table.columns.col}`.