joinspy (version 0.7.3)

check_cartesian: Detect Potential Cartesian Product

Description

Warns if a join will produce a very large result due to many-to-many relationships (Cartesian product explosion).

Usage

check_cartesian(x, y, by, threshold = 10)

Value

A list with explosion analysis.

Arguments

x

A data frame (left table).

y

A data frame (right table).

by

Column names to join by.

threshold

Warn if result will exceed this many times the larger input. Default 10.

See Also

join_spy(), join_strict()

Examples

# Dangerous: both tables have duplicates
x <- data.frame(id = c(1, 1, 2, 2), val_x = 1:4)
y <- data.frame(id = c(1, 1, 2, 2), val_y = 1:4)

check_cartesian(x, y, by = "id")