GDAL-VECTOR-CHECK-GEOMETRY(1)

NAME
gdal-vector-check-geometry - Check a dataset for invalid or non-simple geometries

Added in version 3.12.

SYNOPSIS

            Usage: gdal vector check-geometry [OPTIONS] <INPUT> <OUTPUT>

            Check a dataset for invalid geometries

            Positional arguments:
              -i, --input <INPUT>                                  Input vector datasets [required] [not available in pipelines]
              -o, --output <OUTPUT>                                Output vector dataset [required] [not available in pipelines]

            Common Options:
              -h, --help                                           Display help message and exit
              --json-usage                                         Display usage as JSON document and exit
              --config <KEY>=<VALUE>                               Configuration option [may be repeated]
              -q, --quiet                                          Quiet mode (no progress bar or warning message) [not available in pipelines]

            Options:
              -l, --layer, --input-layer <INPUT-LAYER>             Input layer name(s) [may be repeated] [not available in pipelines]
              -f, --of, --format, --output-format <OUTPUT-FORMAT>  Output format ("GDALG" allowed) [not available in pipelines]
              --co, --creation-option <KEY>=<VALUE>                Creation option [may be repeated] [not available in pipelines]
              --lco, --layer-creation-option <KEY>=<VALUE>         Layer creation option [may be repeated] [not available in pipelines]
              --overwrite                                          Whether overwriting existing output dataset is allowed [not available in pipelines]
              --update                                             Whether to open existing dataset in update mode [not available in pipelines]
              --overwrite-layer                                    Whether overwriting existing output layer is allowed [not available in pipelines]
              --append                                             Whether appending to existing layer is allowed [not available in pipelines]
                                                                   Mutually exclusive with --upsert
              --output-layer <OUTPUT-LAYER>                        Output layer name [not available in pipelines]
              --skip-errors                                        Skip errors when writing features [not available in pipelines]
              --no-create-empty-layers                             Avoid creating layers to which no features will be written [not available in pipelines]
              --include-field <INCLUDE-FIELD>                      Fields from input layer to include in output (special values: ALL and NONE) (default: NONE) [may be repeated]
              --include-valid                                      Include valid inputs in output, with empty geometry
              --geometry-field <GEOMETRY-FIELD>                    Name of geometry field to check

            Advanced Options:
              --if, --input-format <INPUT-FORMAT>                  Input formats [may be repeated] [not available in pipelines]
              --oo, --open-option <KEY>=<VALUE>                    Open options [may be repeated] [not available in pipelines]
              --output-oo, --output-open-option <KEY>=<VALUE>      Output open options [may be repeated] [not available in pipelines]
              --upsert                                             Upsert features (implies 'append') [not available in pipelines]
                                                                   Mutually exclusive with --append

DESCRIPTION

gdal vector check-geometry checks that individual elements of a dataset are valid and simple according to the OGC Simple Features standard. For each invalid or non-simple feature, it will output a description and, in most cases, a point location of the error.

The following checks are performed, depending on the input geometry type:

    •   Polygons and MultiPolygons are checked for validity. A single point error point will be reported even if there are multiple causes of invalidity.

    •   LineStrings and MultiLineStrings are checked for simplicity. All self-intersection locations will be reported if GDAL is built using version 3.14 or later of the GEOS library. With earlier versions, self-intersection locations are not reported.

    •   GeometryCollections are checked that their individual elements are valid / simple. A single error point will be reported even if there are multiple causes of invalidity.

    •   Other geometry types are not checked.

Validity/simplicity checking is performed by the GEOS library and should be consistent with results of software such as PostGIS, QGIS, and shapely that also use that library. GEOS does not consider repeated points to be a cause of invalidity or non-simplicity. For more information about validity testing performed by gdal vector check-geometry, and examples of reported errors, see Geometry Validity.
        [image] Error locations reported by gdal vector check-geometry for Polygon, MultiPolyon, and LineString inputs..UNINDENT

    WARNING:
            Curved geometries are linearized before converting to GEOS. Linearized geometries may be valid/simple where the original geometries are not, and vice-versa.

GDALG OUTPUT (ON-THE-FLY / STREAMED DATASET)

This program supports serializing the command line as a JSON file using the GDALG output format. The resulting file can then be opened as a vector dataset using the GDALG: GDAL Streamed Algorithm driver, and apply the specified pipeline in a on-the-fly / streamed way.

NOTE:
        However this algorithm is not natively streaming compatible. Consequently a in-memory temporary dataset will be generated, which may cause significant processing time at opening.

PROGRAM-SPECIFIC OPTIONS

    --geometry-field
        Specify the name of the geometry field to test, for layers having multiple geometry fields. By default the first geometry field will be used.

    --include-field
        Added in version 3.12.1.

        Optional field(s) to copy from the input features to the output. Since GDAL 3.13, the value ALL can be used to include all fields from the source layer.

    --include-valid
        Include features for valid/simple geometries in the output, maintaining 1:1 correspondence between input and output features.

    --input-layer <INPUT-LAYER>
        Specifies the name of one or more layers to process. By default, all layers will be processed.

    --output-layer
        Specifies the name of the layer to which features will be written. If not specified and there is a single input layer, the name "error_location" will be used. If not specified and there are multiple input layers, features for each input layer will be written to a separate output layer in the format "error_location_{INPUT_LAYER}".

STANDARD OPTIONS

    --append
        Whether appending features to existing layer(s) is allowed. This also creates the output dataset if it does not exist yet.

    --co, --creation-option <NAME>=<VALUE>
        Many formats have one or more optional dataset creation options that can be used to control particulars about the file created. For instance, the GeoPackage driver supports creation options to control the version.

        May be repeated.

        The dataset creation options available vary by format driver, and some simple formats have no creation options at all. A list of options supported for a format can be listed with the --formats command line option but the documentation for the format is the definitive source of information on driver creation options. See Vector drivers format specific documentation for legal creation options for each format.

        Note that dataset creation options are different from layer creation options.

    --if, --input-format <format>
        Format/driver name to be attempted to open the input file(s). It is generally not necessary to specify it, but it can be used to skip automatic driver detection, when it fails to select the appropriate driver. This option can be repeated several times to specify several candidate drivers. Note that it does not force those drivers to open the dataset. In particular, some drivers have requirements on file extensions.

        May be repeated.

    --lco, --layer-creation-option <NAME>=<VALUE>
        Many formats have one or more optional layer creation options that can be used to control particulars about the layer created. For instance, the GeoPackage driver supports layer creation options to control the feature identifier or geometry column name, setting the identifier or description, etc.

        May be repeated.

        The layer creation options available vary by format driver, and some simple formats have no layer creation options at all. A list of options supported for a format can be listed with the --formats command line option but the documentation for the format is the definitive source of information on driver creation options. See Vector drivers format specific documentation for legal creation options for each format.

        Note that layer creation options are different from dataset creation options.

    --no-create-empty-layers
        Added in version 3.13.

        Avoid creating layers to which no features will be written.

    --oo, --open-option <NAME>=<VALUE>
        Dataset open option (format specific).

        May be repeated.

    -f, --of, --format, --output-format <OUTPUT-FORMAT>
        Which output vector format to use. Allowed values may be given by gdal --formats | grep vector | grep rw | sort

    --output-open-option, --output-oo <NAME>=<VALUE>
        Added in version 3.12.

        Dataset open option for output dataset (format specific).

        May be repeated.

    --overwrite
        Allow program to overwrite existing target file or dataset. Otherwise, by default, gdal errors out if the target file or dataset already exists.

    --overwrite-layer
        Whether overwriting the existing output vector layer is allowed.

    --skip-errors
        Added in version 3.12.

        Whether failures to write feature(s) should be ignored. Note that this option sets the size of the transaction unit to one feature at a time, which may cause severe slowdown when inserting into databases.

    --update
        Whether to open an existing output dataset in update mode.

    --upsert
        Added in version 3.12.

        Variant of --append where the OGRLayer::UpsertFeature() operation is used to insert or update features instead of appending with OGRLayer::CreateFeature().

        This is currently implemented only in a few drivers: GPKG -- GeoPackage vector, Elasticsearch: Geographically Encoded Objects for Elasticsearch and MongoDBv3 (drivers that implement upsert expose the GDAL_DCAP_UPSERT capability).

        The upsert operation uses the FID of the input feature, when it is set (and the FID column name is not the empty string), as the key to update existing features. It is crucial to make sure that the FID in the source and target layers are consistent.

        For the GPKG driver, it is also possible to upsert features whose FID is unset or non-significant (the --unset-fid option of gdal vector edit can be used to ignore the FID from the source feature), when there is a UNIQUE column that is not the integer primary key.

RETURN STATUS CODE

The program returns status code 0 in case of success, and non-zero in case of error (non-blocking errors emitted as warnings are considered as a successful execution).

EXAMPLES

  Example 1: Print invalidity locations to console

            $ gdal vector check-geometry ne_10m_admin_0_countries.shp \
                     --quiet \
                     -f CSV \
                     --lco GEOMETRY=AS_XY \
                     --lco SEPARATOR=TAB \
                     /vsistdout/
            # X      Y       error
            # 35.6210871060001       23.1392929140001        Ring Self-intersection

AUTHOR
Dan Baston <dbaston@gmail.com>

COPYRIGHT
1998-2026