> ## Documentation Index
> Fetch the complete documentation index at: https://docs.pysquirrels.com/llms.txt
> Use this file to discover all available pages before exploring further.

# ConnectionTypeEnum

> Enum for connection types

Enumeration of supported connection types in Squirrels.

For example usage, see [ConnectionProperties](/references/python/connections/ConnectionProperties).

This enum can be imported from the `squirrels.connections` or the `squirrels` module.

## Enum values

<ResponseField name="SQLALCHEMY" type="ConnectionTypeEnum">
  SQLAlchemy-based connections using standard database drivers. This is the default connection type and supports the widest range of databases.

  Supports placeholders in SQL queries, using `:param_name` syntax for named parameters.
</ResponseField>

<ResponseField name="DUCKDB" type="ConnectionTypeEnum">
  Native DuckDB connections for fast analytical queries. Use this for DuckDB databases and also for connecting to PostgreSQL, MySQL, and SQLite through DuckDB's connectors.

  Supports placeholders in SQL queries, using `$param_name` syntax for named parameters.
</ResponseField>

<ResponseField name="CONNECTORX" type="ConnectionTypeEnum">
  ConnectorX-based connections for fast data loading from databases. Optimized for bulk data transfers but does not support placeholders in SQL queries.
</ResponseField>

<ResponseField name="ADBC" type="ConnectionTypeEnum">
  Arrow Database Connectivity (ADBC) connections for high-performance data transfer using Apache Arrow. Does not support placeholders in SQL queries.
</ResponseField>