Package org.geotools.data.geoparquet

Class GeoParquetDialect

Object

SQLDialect

BasicSQLDialect

DuckDBDialect

GeoParquetDialect

public class GeoParquetDialect
extends DuckDBDialect

SQL Dialect for GeoParquet format.

This dialect extends the base DuckDB dialect with GeoParquet-specific functionality:

• Parsing and utilizing GeoParquet metadata from the "geo" field
• Setting up appropriate SQL views for GeoParquet files
• Optimizing spatial operations and bounds computations
• Handling both local and remote (HTTP, S3) GeoParquet data access

The dialect extracts and uses the GeoParquet specification metadata to provide improved performance for operations like bounds computation and feature access. It supports both standard GeoParquet format (1.1.0) and development versions (1.2.0-dev).

Field Summary

Fields inherited from class SQLDialect

BASE_DBMS_CAPABILITIES, dataStore, forceLongitudeFirst, UNWRAPPER_NOT_FOUND, uwMap

Constructor Summary

Constructors

Constructor	Description
GeoParquetDialect(JDBCDataStore dataStore, URI uri)

Method Summary

Modifier and Type	Method	Description
FilterToSQL	createFilterToSQL()	Creates the filter encoder to be used by the datastore when encoding query predicates.
List<String>	getConnectionInitSqls()	Connection init scripts to work with geoparquet
Integer	getGeometrySRID(String schemaName, String tableName, String columnName, Connection cx)	Returns the spatial reference system identifier (srid) for a particular geometry column.
GeoparquetDatasetMetadata	getGeoparquetMetadata(Connection cx)
List<ReferencedEnvelope>	getOptimizedBounds(String schema, SimpleFeatureType featureType, Connection cx)	If possible, return the full dataset bounds from the geo geoparquet metadata field.
PrimaryKeyFinder	getPrimaryKeyFinder()	Helper for GeoParquetDataStoreFactory to identify the id column as the primary key (and hence the FeatureId)
void	initializeConnection(Connection cx)	Initializes a newly created database connection.
Map<String,GeoParquetMetadata>	loadGeoparquetMetadata(Connection cx)
void	registerParquetViews()

Methods inherited from class DuckDBDialect

addSupportedHints, applyLimitOffset, decodeGeometryEnvelope, decodeGeometryValue, encodeColumnName, encodeGeometryColumn, encodeGeometryColumnGeneralized, encodeGeometryColumnSimplified, encodeGeometryEnvelope, encodeGeometryValue, encodePostColumnCreateTable, encodePrimaryKey, escapeName, getMapping, getNameEscape, includeTable, isConcreteGeometry, isLimitOffsetSupported, optimizedBounds, parseWKB, parseWKB, registerClassToSqlMappings, setScreenMapEnabled, setSimplifyEnabled

Methods inherited from class BasicSQLDialect

encodeValue, onDelete, onInsert, onSelect, onUpdate

Methods inherited from class SQLDialect

applyHintsOnVirtualTables, canGroupOnGeometry, canSimplifyPoints, convertValue, createCRS, createIndex, decodeGeometryValue, dropIndex, encodeColumnAlias, encodeColumnName, encodeColumnType, encodeCreateTable, encodeJoin, encodeNextSequenceValue, encodePostCreateTable, encodePostSelect, encodeSchemaName, encodeTableAlias, encodeTableName, getAggregateConverter, getDefaultVarcharSize, getDesiredTablesType, getGeometryDimension, getGeometryTypeName, getIndexes, getLastAutoGeneratedValue, getLastAutoGeneratedValue, getMapping, getNextAutoGeneratedValue, getNextSequenceValue, getPkColumnValue, getPrimaryKey, getRestrictions, getResultTypes, getSequenceForColumn, getSQLType, handleSelectHints, handleUserDefinedType, isAggregatedSortSupported, isArray, isAutoCommitQuery, isGroupBySupported, lookupGeneratedValuesPostInsert, ne, postCreateAttribute, postCreateFeatureType, postCreateTable, postDropTable, preDropTable, registerAggregateFunctions, registerSqlTypeNameToClassMappings, registerSqlTypeToClassMappings, registerSqlTypeToSqlTypeNameOverrides, splitFilter, supportsSchemaForIndex, unwrapConnection

Methods inherited from class Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

GeoParquetDialect

public GeoParquetDialect(JDBCDataStore dataStore,
                         URI uri)

Method Detail

initializeConnection

public void initializeConnection(Connection cx)
                          throws SQLException

Description copied from class: SQLDialect

Initializes a newly created database connection.

Subclasses should override this method if there is some additional action that needs to be taken when a new connection to the database is created. The default implementation does nothing.

Overrides:

initializeConnection in class SQLDialect

Parameters:

cx - The new database connection.

Throws:

SQLException

createFilterToSQL

public FilterToSQL createFilterToSQL()

Description copied from class: BasicSQLDialect

Creates the filter encoder to be used by the datastore when encoding query predicates.

Sublcasses can override this method to return a subclass of FilterToSQL if need be.

Overrides:

createFilterToSQL in class DuckDBDialect

getConnectionInitSqls

public List<String> getConnectionInitSqls()

Connection init scripts to work with geoparquet

Overrides:

getConnectionInitSqls in class DuckDBDialect

getGeoparquetMetadata

public GeoparquetDatasetMetadata getGeoparquetMetadata(Connection cx)
                                                throws IOException

Throws:

IOException

loadGeoparquetMetadata

public Map<String,GeoParquetMetadata> loadGeoparquetMetadata(Connection cx)
                                                            throws IOException

Throws:

IOException

getPrimaryKeyFinder

public PrimaryKeyFinder getPrimaryKeyFinder()

Helper for GeoParquetDataStoreFactory to identify the id column as the primary key (and hence the FeatureId)

getOptimizedBounds

public List<ReferencedEnvelope> getOptimizedBounds(String schema,
                                                   SimpleFeatureType featureType,
                                                   Connection cx)
                                            throws SQLException,
                                                   IOException

If possible, return the full dataset bounds from the geo geoparquet metadata field.

Otherwise check if there's a bbox column even if the geoparquet metadata is not present (e.g. OvertureMaps release 2025-02-19.0), and compute the xmin,xmax,ymin,ymax bounds using aggregate functions, which will perform better since it uses the column stats.

Finally, fall back to DuckDBDialect.getOptimizedBounds(String, SimpleFeatureType, Connection) for a more general (and slow) ST_Extent_Agg(geometry) call.

Overrides:

getOptimizedBounds in class DuckDBDialect

Parameters:

schema - The database schema, if any, or null

featureType - The feature type containing the geometry columns whose bounds need to computed. Mind, it may be retyped and thus contain less geometry columns than the table

Returns:

a list of referenced envelopes (some of which may be null or empty)

Throws:

SQLException

IOException

registerParquetViews

public void registerParquetViews()
                          throws IOException

Throws:

IOException

getGeometrySRID

public Integer getGeometrySRID(String schemaName,
                               String tableName,
                               String columnName,
                               Connection cx)
                        throws SQLException

Description copied from class: SQLDialect

Returns the spatial reference system identifier (srid) for a particular geometry column.

This method is given a direct connection to the database. The connection must not be closed. However any statements or result sets instantiated from the connection must be closed.

In the event that the srid cannot be determined, this method should return null .

Overrides:

getGeometrySRID in class DuckDBDialect

Parameters:

schemaName - The database schema, could be null.

tableName - The table, never null.

columnName - The column name, never null

cx - The database connection.

Throws:

SQLException