5. Exporting and Converting Spatial Data

5.1. Introduction

5.2. Learning Objectives

5.3. Sample Datasets

5.4. Installation and Setup

5.4.1. Library Import and Initial Setup

5.5. Installing and Loading Extensions

5.6. Loading Sample Data

5.7. Exporting to Pandas DataFrames

5.7.1. Basic DataFrame Export

5.7.2. Exporting Filtered Query Results

5.7.3. Working with Geometry Columns in DataFrames

5.7.4. Converting Geometries to Text for DataFrames

5.7.5. Integrating with GeoPandas for Spatial Operations

5.7.6. Performance Considerations for DataFrame Export

5.8. Exporting to CSV Files

5.8.1. Basic CSV Export

5.8.2. Streaming Query Results to CSV

5.8.3. Handling Geometries in CSV Exports

5.8.4. When to Use CSV Export

5.9. Exporting to JSON Files

5.9.1. Basic JSON Export

5.9.2. Exporting Filtered Query Results to JSON

5.9.3. Handling Geometries in JSON Exports

5.9.4. When to Use JSON Export

5.10. Exporting to Excel Files

5.10.1. Install the excel extension

5.10.2. Installing and Loading the Excel Extension

5.10.3. Basic Excel Export Without Geometries

5.10.4. Including Spatial Information as Text Columns

5.10.5. Exporting Filtered and Aggregated Results to Excel

5.10.6. When to Use Excel Export

5.11. Exporting to Parquet Files

5.11.1. Key Advantages of Parquet

5.11.2. Basic Parquet Export

5.11.3. Exporting Filtered Query Results to Parquet

5.11.4. Partitioned Parquet Writes

5.12. Exporting to GeoJSON Format

5.12.1. GeoJSON Structure and GDAL Integration

5.12.2. Basic GeoJSON Export

5.12.3. Exporting Filtered Subsets to GeoJSON

5.12.4. Customizing GeoJSON Export Options

5.12.5. When to Use GeoJSON

5.12.6. Limitations and When to Avoid GeoJSON

5.13. Exporting to Shapefile Format

5.13.1. Shapefile Limitations and Constraints

5.13.2. Why GeoPackage is Preferred

5.13.3. Shapefile Export Syntax

5.14. Exporting to GeoPackage Format

5.14.1. Advantages of GeoPackage Over Legacy Formats

5.14.2. Basic GeoPackage Export

5.14.3. Exporting Filtered Subsets to GeoPackage

5.14.4. When to Use GeoPackage Export

5.15. Key Takeaways

5.16. Exercises

5.16.1. Exercise 1: Basic CSV Export with Geometry Handling

5.16.2. Exercise 2: Filtered Exports to Multiple Formats

5.16.3. Exercise 3: DataFrame Export and Manipulation

5.16.4. Exercise 4: Exporting with Spatial Aggregations

5.16.5. Exercise 5: GeoJSON Export for Web Mapping

5.16.6. Exercise 6: GeoPackage Export for GIS Interoperability

5.16.7. Exercise 7: Partitioned Parquet Export

5.16.8. Exercise 8: Excel Export with Readable Geometries

5.16.9. Exercise 9: Round-Trip Export and Import

5.16.10. Exercise 10: Comprehensive Export Pipeline Challenge