PG: faster information retrieval for table info

[elpaso]

Information about single tables does not need to
scan for all tables anymore.

Fix #56069

[github-actions]

🪟 Windows builds ready!

Windows builds of this PR are available for testing here. Debug symbols for this build are available here.

(Built from commit 46a5ddd)

[strk]

I appreciate the goal of this PR but adding another parameter to the existing overcomplex function doesn't seem the best approach here. Had you considered creating a new simplified function to fetch info about a single table ? Parameters like "searchGeometryColumnsOnly" or "searchPublicOnly" do not make any sense with a function that's asked for a specific table

[nyalldawson]

Thanks, I've bumped into this as well when accessing slow remote databases!

[kannes]

Thank you so much, @elpaso and @rouault . This will safe lots of unnecessarily burned resources :)

[kannes]

Any chance to get this backported into 3.34 (so it lands in LTR soonish) in exchange for some German Marzipan if I make to Slovakia in September? 😊

[qgis-bot]

The backport to release-3_34 failed:

The process '/usr/bin/git' failed with exit code 1

stderr

error: could not apply 1ed4113ef1c... PG: faster information retrieval for table info
hint: After resolving the conflicts, mark them with
hint: "git add/rm <pathspec>", then run
hint: "git cherry-pick --continue".
hint: You can instead skip this commit with "git cherry-pick --skip".
hint: To abort and get back to the state before "git cherry-pick",
hint: run "git cherry-pick --abort".

stdout

Auto-merging src/providers/postgres/qgspostgresconn.cpp
CONFLICT (content): Merge conflict in src/providers/postgres/qgspostgresconn.cpp
Auto-merging src/providers/postgres/qgspostgresproviderconnection.cpp
CONFLICT (content): Merge conflict in src/providers/postgres/qgspostgresproviderconnection.cpp

To backport manually, run these commands in your terminal:

# Fetch latest updates from GitHub
git fetch
# Create a new working tree
git worktree add .worktrees/backport-release-3_34 release-3_34
# Navigate to the new working tree
cd .worktrees/backport-release-3_34
# Create a new branch
git switch --create backport-56090-to-release-3_34
# Cherry-pick the merged commit of this pull request and resolve the conflicts
git cherry-pick 1ed4113ef1c60ef612e4855c091b80f52ece5c4b,f182d76615f521c514d0a507b8891fe382d780c5,c4898c1fede5a113f52a86de247f2bc77e120484,46a5ddd25164408fe35e0bc5340663d2f813864d
# Push it to GitHub
git push --set-upstream origin backport-56090-to-release-3_34
# Go back to the original working tree
cd ../..
# Delete the working tree
git worktree remove .worktrees/backport-release-3_34

Then, create a pull request where the base branch is release-3_34 and the compare/head branch is backport-56090-to-release-3_34.