PostGIS
Mobile
QGIS
MapBender
GeoServer
GeoNode
GeoNetwork
Novella
Solutions
80 lines
1.7 KiB
Markdown
80 lines
1.7 KiB
Markdown
# Create View Worker
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Processes view creation jobs to create database views from queries.
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## Overview
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The create view worker creates database views based on SQL queries, allowing dynamic datasets that update when source data changes.
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## Job Type
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`create_view`
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## Input Parameters
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```json
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{
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"source_dataset_id": 123,
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"query": "SELECT * FROM spatial_data_123 WHERE properties->>'category' = 'A'",
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"output_dataset_id": 124
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}
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```
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### Parameters
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- `source_dataset_id` (required): Source dataset ID
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- `query` (required): SQL query to create view from
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- `output_dataset_id` (required): Output dataset ID
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## Output
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Creates a new dataset backed by a database view:
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- View created in `spatial_data` schema
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- Dataset metadata in `spatial_files` table
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- View updates automatically when source data changes
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## Use Cases
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- Filtered datasets
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- Joined datasets
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- Aggregated datasets
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- Computed datasets
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## Example
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```bash
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# Enqueue a create view job via API
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curl -X POST "https://example.com/api/create_view_run.php" \
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-H "Content-Type: application/json" \
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-d '{
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"source_dataset_id": 123,
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"query": "SELECT * FROM spatial_data_123 WHERE properties->>'\''category'\'' = '\''A'\''",
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"output_dataset_id": 124
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}'
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```
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## Background Jobs
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This analysis runs as a background job. The worker:
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1. Fetches queued `create_view` jobs
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2. Validates input parameters
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3. Validates SQL query
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4. Creates database view
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5. Creates dataset metadata
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6. Marks job as completed
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## Performance Considerations
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- Views don't store data, so creation is fast
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- Query performance depends on underlying data
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- Complex queries may slow view access
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- Consider materialized views for expensive queries
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## Related Documentation
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- [Analysis API](../api/analysis.md)
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- [Workers Overview](index.md)
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