dbplyr 2.1.0

New features

• Thanks to @mgirlich, dbplyr gains support for key verbs from tidyr:
  pivot_longer() (#532), pivot_wider() (#543), expand() (#538),
  complete() (#538), replace_na() (#538), fill() (#566).

• @mgirlich is now a dbplyr author in recognition of his significant and
  sustained contributions.

• across() implementation has been rewritten to support more inputs:
  it now translates formulas (#525), works with SQL functions that don't have
  R translations (#534), and work with NULL (#554)

• summarise() now supports argument .groups (@mgirlich, #584).

SQL translation

• All backends: str_sub(), substr() and substring() get better
  translations (#577). Most importantly, the results of using negative
  locations should match the underlying R implementations more closely.

• MS SQL:

  • as.integer() and as.integer64() translations cast first to NUMERIC
    to avoid CASTing weirdness (@DavidPatShuiFong, #496).

  • Assumes a boolean context inside of [ (#546)

  • str_sub() with end = -1 now works (#577).

• Redshift: lag() and lead() lose the default parameter since it's
  not supported (@hdplsa, #548).

• SQLite: custom translation of full_join() and right_join()
  (@mgirlich, #536).

Minor improvements and bug fixes

• RPostgreSQL backend warns if temporary = TRUE since temporary tables are
  not supported by RPostgres::dbWriteTable() (#574).

• count() method provides closer match to dplyr semantics (#347).

• distinct() now respects grouping (@mgirlich, #535).

• db_connection_describe() no longer uses partial matching (@mgirlich, #564).

• pull() no longer select()s the result when there's already only
  one variable (#562).

• select() no longer relocates grouping variables to the front
  (@mgirlich, #568). and informs when adding missing grouping variables
  (@mgirlich, #559).

• tbl.src_dbi(...) now passed on to tbl_sql() (#530).