Skip to content

Configuring a DuckDB Data Store

Creating a DuckDB Store

  1. Navigate to Stores > Add new Store.
  2. Select DuckDB.
  3. Fill in the connection parameters.
  4. Save the store and publish layers from the discovered feature types.

Connection Parameters

The following screenshot shows the DuckDB store form in GeoServer:


DuckDB store configuration form.

The following parameters are relevant for DuckDB:
dbtype Must be duckdb.
memory If true, use an in-memory DuckDB database. Default is false.
database Path to the DuckDB database file. Required when memory=false. Must be omitted when memory=true.
read_only Enables read-only mode for the store. Default is true. Set to false to allow write operations.
simplification Enables SQL-side geometry simplification when rendering/query hints request it. Default is true.
screenmap Enables screenmap rendering optimization to skip features that fall in already painted screen pixels. Default is true.
namespace Namespace URI used for published feature types.
fetch size JDBC fetch size hint for result streaming.

Storage Configuration Rules

DuckDB store configuration enforces the following:

  • memory and database are mutually exclusive.
  • If memory=false, database is required.
  • If memory=true, database must not be provided.

Security Model

The DuckDB datastore in GeoServer uses a guarded execution policy from GeoTools:

  • Store instances are read-only by default (read_only=true).
  • SQL execution is restricted to approved statement categories.
  • Session script style SQL and multi-statement SQL are blocked.
  • User-defined SQL view workflows are not supported for DuckDB stores.

Write Mode

To enable writes for a specific store, set read_only=false.

When write mode is enabled, GeoTools can execute managed DDL/DML statements required by datastore operations. Keep this disabled unless you explicitly need write behavior.