Package org.geotools.data.geoparquet

Class GeoParquetFilterToSQL

  • All Implemented Interfaces:
    ExpressionVisitor, FilterVisitor
    public class GeoParquetFilterToSQL
extends DuckDBFilterToSQL
    Filter SQL encoder for GeoParquet queries.

    This class extends DuckDBFilterToSQL with GeoParquet-specific optimizations for encoding OGC Filter objects into SQL queries. It handles translation of spatial filters, particularly optimizing bounding box (BBOX) queries to work efficiently with GeoParquet's metadata and structure.

    Key features include:

    • Optimized BBOX filter translation that uses GeoParquet's bounding box information
    • Support for the standard set of spatial operations adapted to GeoParquet's spatial model

    The implementation specifically targets the column structure and query patterns that perform well with GeoParquet datasets, considering both the GeoParquet specification and DuckDB's spatial capabilities.

    • Constructor Detail

      • GeoParquetFilterToSQL

        public GeoParquetFilterToSQL()

    • Method Detail

      • toString

        public String toString()
        Returns a string representation of this filter encoder.
        Overrides:
        toString in class Object
        Returns:
        A string representation showing the current SQL output

      • visitBBOX

        protected Object visitBBOX​(BBOX filter,
                           Expression leftExp,
                           Expression rightExpt,
                           Object extraData)
        Converts a bounding box filter to optimized SQL using bbox components.

        This method optimizes bounding box queries by using the 'bbox' column components common in GeoParquet datasets. Instead of using expensive spatial functions, it uses simple comparisons on the xmin, xmax, ymin, ymax components, which can be much more efficient.

        The generated SQL follows the pattern: bbox.xmin <= maxX and bbox.xmax >= minX and bbox.ymin <= maxY and bbox.ymax >= minY which implements a proper spatial intersection test using only simple comparisons.

        Overrides:
        visitBBOX in class DuckDBFilterToSQL
        Parameters:
        filter - The BBOX filter to encode
        leftExp - The left expression (typically the geometry column)
        rightExpt - The right expression (typically the literal bounding box)
        extraData - Extra data that might be passed through
        Returns:
        The extraData parameter, potentially modified