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Set column comments on a DuckLake table

Source: R/comments.R
set_column_comments.Rd

Stores per-column descriptions in the DuckLake catalog with COMMENT ON COLUMN, one name = "comment" pair per column. For data with haven/labelled variable labels, create_table() can store the labels automatically; this function adds or revises them afterward – for example to label a derived variable.

Usage

set_column_comments(table_name, ...)

Arguments

table_name

The table whose columns to describe.

...

Named comments, e.g. USUBJID = "Unique subject identifier". Use NA (or NULL) as a value to clear that column's comment. To pass a named vector built elsewhere, splice it with do.call(set_column_comments, c(list("tbl"), as.list(my_labels))).

Value

Invisibly returns NULL.

Details

All comments from one call are written in a single transaction, so they land as one snapshot. Inside with_transaction() they join the open transaction instead.

See also

set_table_comment(), get_table_comments()

Other table documentation: get_table_comments(), set_table_comment()

Examples

if (FALSE) { # \dontrun{
set_column_comments(
  "adsl",
  USUBJID = "Unique subject identifier",
  AGEGR1 = "Age group 1",
  SCRATCH = NA  # clear this one
)
} # }