Learn R Programming

dm (version 0.2.8)

dplyr_join: dplyr join methods for zoomed dm objects

Description

Use these methods without the '.zoomed_dm' suffix (see examples).

Usage

# S3 method for zoomed_dm
left_join(x, y, by = NULL, copy = NULL, suffix = NULL, select = NULL, ...)

# S3 method for zoomed_dm inner_join(x, y, by = NULL, copy = NULL, suffix = NULL, select = NULL, ...)

# S3 method for zoomed_dm full_join(x, y, by = NULL, copy = NULL, suffix = NULL, select = NULL, ...)

# S3 method for zoomed_dm right_join(x, y, by = NULL, copy = NULL, suffix = NULL, select = NULL, ...)

# S3 method for zoomed_dm semi_join(x, y, by = NULL, copy = NULL, suffix = NULL, select = NULL, ...)

# S3 method for zoomed_dm anti_join(x, y, by = NULL, copy = NULL, suffix = NULL, select = NULL, ...)

Arguments

x, y

tbls to join. x is the zoomed_dm and y is another table in the dm.

by

If left NULL (default), the join will be performed by via the foreign key relation that exists between the originally zoomed table (now x) and the other table (y). If you provide a value (for the syntax see dplyr::join), you can also join tables that are not connected in the dm.

copy

Disabled, since all tables in a dm are by definition on the same src.

suffix

Disabled, since columns are disambiguated automatically if necessary, changing the column names to table_name.column_name.

select

Select a subset of the RHS-table's columns, the syntax being select = c(col_1, col_2, col_3) (unquoted or quoted). This argument is specific for the join-methods for zoomed_dm. The table's by column(s) are automatically added if missing in the selection.

Examples

Run this code
# NOT RUN {
flights_dm <- dm_nycflights13()
dm_zoom_to(flights_dm, flights) %>%
  left_join(airports, select = c(faa, name))

# this should illustrate that tables don't necessarily need to be connected
dm_zoom_to(flights_dm, airports) %>%
  semi_join(airlines, by = "name")
# }

Run the code above in your browser using DataLab