rolap (version 2.5.1)

get_existing_fact_instances: Get existing fact instances

Description

From the planned update, it obtains the instances of the update facts that are already included in the star database facts to be updated.

Usage

get_existing_fact_instances(sdbu)
# S3 method for star_database_update
get_existing_fact_instances(sdbu)

Value

A tibble object.

Arguments

sdbu

A star_database_update object.

Details

The most common thing is that refresh operations only include new instances in fact tables, but it may be the case that repeated instances appear: They may have different values in the measures, but the same values in the dimension foreign keys. When the update occurs, we need to determine what happens to these instances.

See Also

star_database

Other star database refresh functions: get_lookup_tables(), get_new_dimension_instances(), get_star_database(), get_star_schema(), get_transformation_code(), get_transformation_file(), incremental_refresh(), update_according_to()

Examples

f1 <-
  flat_table('ft_num', ft_cause_rpd[ft_cause_rpd$City != 'Cambridge' &
                                      ft_cause_rpd$WEEK != '4',]) |>
  as_star_database(mrs_cause_schema_rpd) |>
  role_playing_dimension(rpd = "When",
                         roles = c("When Available", "When Received"))
f2 <- flat_table('ft_num2', ft_cause_rpd[ft_cause_rpd$City != 'Bridgeport' &
                                           ft_cause_rpd$WEEK != '2',])
f2 <- f2 |>
  update_according_to(f1)
fact_instances <- f2 |>
  get_existing_fact_instances()