2 Commits (0ca70e9d4321b9c6e244e90519901fe9bff46861)

Author	SHA1	Message	Date
Dmitry S	95320f3f5b	(core) Update documentation for lookup/find/prevnext for the Help Center ... Summary: Documentation in https://github.com/gristlabs/grist-help/ is built using `./build-functions.sh`, and the current version (as updated and landed in https://github.com/gristlabs/grist-help/pull/368) already reflects the changes in this diff. Test Plan: No changes to functionality, only documentation comments. Reviewers: jarek Reviewed By: jarek Differential Revision: https://phab.getgrist.com/D4306	2 months ago
Dmitry S	f0d0a07295	(core) Implement PREVIOUS/NEXT/RANK and lookupRecords().find.* methods. ... Summary: - `lookupRecords()` now allows efficient search in sorted results, with the syntax `lookupRecords(..., order_by="-Date").find.le($Date)`. This will find the record with the nearest date that's <= `$Date`. - The `find.*` methods are `le`, `lt`, `ge`, `gt`, and `eq`. All have O(log N) performance. - `PREVIOUS(rec, group_by=..., order_by=...)` finds the previous record to rec, according to `group_by` / `order_by`, in amortized O(log N) time. For example, `PREVIOUS(rec, group_by="Account", order_by="Date")`. - `PREVIOUS(rec, order_by=None)` finds the previous record in the full table, sorted by the `manualSort` column, to match the order visible in the unsorted table. - `NEXT(...)` is just like `PREVIOUS(...)` but finds the next record. - `RANK(rec, group_by=..., order_by=..., order="asc")` returns the rank of the record within the group, starting with 1. Order can be `"asc"` (default) or `"desc"`. - The `order_by` argument in `lookupRecords`, and the new functions now supports tuples, as well as the "-" prefix to reverse order, e.g. `("Category", "-Date")`. - New functions are only available in Python3, for a minor reason (to support keyword-only arguments for `group_by` and `order_by`) and also as a nudge to Python2 users to update. - Includes fixes for several situations related to lookups that used to cause quadratic complexity. Test Plan: - New performance check that sorted lookups don't add quadratic complexity. - Tests added for lookup find.* methods, and for PREVIOUS/NEXT/RANK. - Tests added that renaming columns updates `order_by` and `group_by` arguments, and attributes on results (e.g. `PREVIOUS(...).ColId`) appropriately. - Python3 tests can now produce verbose output when VERBOSE=1 and -v are given. Reviewers: jarek, georgegevoian Reviewed By: jarek, georgegevoian Subscribers: paulfitz, jarek Differential Revision: https://phab.getgrist.com/D4265	2 months ago