Performance improvements for calendar

• DO not load calendar feeds that are disabled
• Do not load all calendar feeds when loading calendar view
• Pass on calendar client request date range as far dow nas possible, e.g. to Person query for birthday feed
• Evaluate recurrences on database level
• Use indizes

assigned to @hansegucker

added part::frontend type::bug labels

created branch 891-performance-improvements-for-calendar to address this issue

mentioned in merge request !1354 (closed)

added board::todo label

assigned to @nik and unassigned @hansegucker

marked the checklist item DO not load calendar feeds that are disabled as completed

marked the checklist item Do not load all calendar feeds when loading calendar view as completed

@nik investigates whether evaluating of rrules directly in PostgreSQL (via extension) is possible.

changed the description

added 1 deleted label

closed

marked the checklist item Use indizes as completed

marked the checklist item Evaluate recurrences on database level as completed

marked the checklist item Pass on calendar client request date range as far dow nas possible, e.g. to Person query for birthday feed as completed