ADBC -- Arrow Database Connectivity

Added in version 3.11.

Driver short name

ADBC

ADBC is a set of APIs and libraries for Arrow-native access to database.

This driver has 2 modes:

either it has been built against the adbc-driver-manager library. In that case, it can directly be used to connect to available ADBC drivers, and expose content as classic OGR features, or as a ArrowArrayStream. In that mode the driver metadata exposes the HAS_ADBC_DRIVER_MANAGER metadata item.
or it has not, in which case applications embedding GDAL must use GDALSetAdbcLoadDriverOverride() as detailed in a below paragraph. Note that use of that function can also be done even if the driver has been built against the adbc-driver-manager library.

Consult the installation instruction for the various ADBC drivers. At time of writing, there are drivers for SQLite3, PostgreSQL, Snowflake, BigQuery, DuckDB, Flight SQL, etc.

The driver is read-only, and there is no support for spatial data currently.

Connection string

Several connection strings are supported:

ADBC:{some_uri}, together with the ADBC_DRIVER open option.
a SQLite3 database filename, if the adbc_driver_sqlite is available.
a DuckDB database filename, if the libduckdb.so, libduckdb.dylib or duckdb.dll is available (and it is in a system location, or can be located through LD_LIBRARY_PATH on Linux, DYLD_LIBRARY_PATH on MacOSX or PATH on Windows).
a Parquet database filename, if the libduckdb.so, libduckdb.dylib or duckdb.dll is available (and it is in a system location, or can be located through LD_LIBRARY_PATH on Linux, DYLD_LIBRARY_PATH on MacOSX or PATH on Windows).
a PostgreSQL URI starting with postgresql://, if the adbc_driver_postgresql is available.

Note: if present, the SQLite / Spatialite RDBMS, GPKG -- GeoPackage vector or (Geo)Parquet drivers are registered before the ADBC driver, so they will be used in priority when available. The ADBC: prefix or the -if ADBC switch of ogrinfo or ogr2ogr can be used to use the ADBC driver instead.

Dataset open options

Open options can be specified in command-line tools using the syntax -oo <NAME>=<VALUE> or by providing the appropriate arguments to GDALOpenEx() (C) or gdal.OpenEx (Python). The following open options are supported:

ADBC_DRIVER=<string>: ADBC driver name. Examples: adbc_driver_sqlite, adbc_driver_postgresql, adbc_driver_bigquery, adbc_driver_snowflake or a path to the DuckDB shared library.
SQL=<string>: A SQL-like statement recognized by the driver, used to create a result layer from the dataset.
ADBC_OPTION_xxx=<string>: Custom ADBC option to pass to AdbcDatabaseSetOption(). Options are driver specific. For example ADBC_OPTION_uri=some_value to pass the uri option.
PRELUDE_STATEMENTS=<string>: SQL-like statement recognized by the driver that must be executed before discovering layers. Can be repeated multiple times. For example PRELUDE_STATEMENTS=INSTALL spatial and PRELUDE_STATEMENTS=LOAD spatial to load DuckDB spatial extension.

"table_list" special layer

For PostgreSQL, SQLite3, DuckDB and Parquet datasets, the driver automatically instantiates OGR layers from available tables. For other databases, the user must explicit provide a SQL open option or issue a GDALDataset::ExecuteSQL() request. To facilitate that process, a special OGR table_list layer can be queried through GDALDataset::GetLayerByName() (or as the layer name with ogrinfo). It returns for each table a OGR feature with the following fields (some potentially unset or with an empty string): catalog_name, schema_name, table_name, table_type.

Custom driver entry point

A custom driver entry point can be specified by applications by calling GDALSetAdbcLoadDriverOverride() (defined in header gdal_adbc.h) before using the driver. The specified init function will be used by the GDAL ADBC driver as a way of locating and loading the ADBC driver if GDAL was not built with ADBC Driver Manager support or if an embedding application has an updated or augmented collection of drivers available.

Examples

Assuming libduckdb.so, libduckdb.dylib or duckdb.dll is available (and it is in a system location, or can be located through LD_LIBRARY_PATH on Linux, DYLD_LIBRARY_PATH on MacOSX or PATH on Windows).

Convert a Parquet file to GeoPackage:
```
ogr2ogr out.gpkg in.parquet
```
Assuming libduckdb.so, libduckdb.dylib or duckdb.dll is available (and it is in a system location, or can be located through LD_LIBRARY_PATH on Linux, DYLD_LIBRARY_PATH on MacOSX or PATH on Windows).

Convert a DuckDB database to GeoPackage:
```
ogr2ogr out.gpkg in.duckdb
```