Merge a CrunchDataFrame

mergeing a CrunchDataFrame with a local dataframe is useful in situations where you have new information in your local R session that you want to connect with Crunch data. For example, for making plots with Crunch and non-Crunch data. It produces a hybrid CrunchDataFrame that has the local data attached to it, but like normal CrunchDataFrames it is still judicious about downloading data from the server only when it is needed.

# S3 method for CrunchDataFrame
merge(
  x,
  y,
  by = intersect(names(x), names(y)),
  by.x = by,
  by.y = by,
  sort = c("x", "y"),
  ...
)

Arguments

x

a CrunchDataFrame

y

a standard data.frame

by

name of the variable to match in both data sources (default: the intersection of the names of x and y)

by.x

name of the variable to match in x

by.y

name of the variable to match in y

sort

character, either "x" or "y" (default: "x"). Which of the inputs should be used for the output order. Unlike merge.data.frame, merge.CrunchDataFrame will not re-sort the order of the output. It will use the order of either x or y.

...

ignored

Value

a CrunchDataFrame with columns from both x and y

Details

Merging a CrunchDataFrame with a local dataframe does not allow specifying all rows from both sources. Instead, the resulting CrunchDataFrame will include all of the rows in whichever source is used for sorting (x or y). So if you specify sort="x" (the default) all rows of x will be present but rows in y that do not match with rows in x will not be present.

Merging a CrunchDataFrame with a local dataframe is experimental and might result in unexpected results. One known issue is that using merge on a CrunchDataFrame will change the both the CrunchDataFrame used as input as well as create a new CrunchDataFrame.