OPAL Projection Verbs

Projection verbs create, remove, or rename columns in a dataset.

Verb	Description
drop_col	Exclude one or more columns from the input dataset to the output dataset.
extract_regex	Add one or more columns by matching capture names in a regular expression against a given source expression.
make_col	Add one or more new columns from the input dataset to the output dataset.
pick_col	Exclude all columns except the specified columns from the input dataset to the output dataset.
rename_col	Include all columns while renaming the specified columns from the input dataset to the output dataset.