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QGIS Documentation
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HANA Provider: Add support for fast extent estimation (Request in QGIS) #9143

Open qgis-bot opened 1 week ago

qgis-bot commented 1 week ago

Request for documentation

From pull request qgis/QGIS#57654 Author: @jatsqi QGIS version: 3.38

HANA Provider: Add support for fast extent estimation

PR Description:

Description

With QRC/1 2024 a new and faster way to estimate extents of spatial column has been added to HANA. More precisely, users can now use special columns in this table to get an estimation of the extent of a spatial column. Even though the stored extent is only an estimation, it is often good enough. Especially for very large tables costly aggregation functions are avoided every time the extent is recomputed. The extent information in the mentioned HANA table is only available after a delta-merge, so a fallback to the standard behaviour, i.e. via aggregation functions, was added in case the data is unavailable or has not yet been computed.

Summary of changes:

  1. Support for the mentioned fast extent estimation added
  2. Fallback in case of unavailability added
  3. Checkbox to enable behaviour added to HANA connection widget (see image down below, 'Use estimated table metadata')

image

Commits tagged with [need-docs] or [FEATURE]

jatsqi commented 6 days ago

Hi, I already opened a PR for this (https://github.com/qgis/QGIS-Documentation/pull/9142). This should include all necessary changes to the public documentation.

selmaVH1 commented 6 days ago

Thank you @jatsqi