web/links/index.htm: updated to Firefox bookmarks: PostgreSQL: query planner: documented how to prevent incorrect query plans (`SET enable_seqscan = off;`, etc.)

web/links/index.htm: updated to Firefox bookmarks: PostgreSQL: query planner: documented that incorrect query plans are an ongoing bug in Postgres, because it does not support index hints and by default does not follow the join order. specifically, Postgres often does the following things in query plans which should normally never be done:...

schemas/vegbien.sql, inputs/SALVIAS/validations.sql: added _plots_06a_list_of_stems, for use in figuring out the diff in _plots_06_list_of_plots_with_stem_measurements

validation/aggregating/plots/bien3_validations_salvias_vegbien.sql: updated to DB

schemas/vegbien.sql: plot: removed explicit column lists added in the autorename of plot.location_id->plot_id

schemas/vegbien.sql: plot: renamed pkey to plot_id. note that the field is autorenamed in all validation views which use it.

schemas/vegbien.sql: locationevent: added autopopulated plot_id column which points to the outermost plot of the locationevent's location

bugfix: schemas/vegbien.sql: locationevent: added missing fkey on place_visit_id

bugfix: schemas/vegbien.sql: _plots_06_list_of_plots_with_stem_measurements: only include stemobservation records which have actual stem IDs, not merely stem-related measurements (DBH, etc.)

validation/aggregating/plots/bien3_validations_salvias_vegbien.sql: added `SET enable_seqscan = off;` to match what is done by rematerialize_out_view() to run the queries properly