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Add a column to a DuckLake table

Source: R/schema_evolution.R
add_table_column.Rd

Adds a column in place with ALTER TABLE ... ADD COLUMN. This is a metadata-only change: no data files are rewritten, history is preserved, and earlier snapshots still show the old schema. Compare replace_table(), which collects the table into R and rewrites it.

Usage

add_table_column(table_name, column_name, type, default = NULL)

Arguments

table_name

The table to change.

column_name

Name of the new column.

type

SQL type for the new column, e.g. "INTEGER", "DECIMAL(10,2)", or "TIMESTAMP WITH TIME ZONE".

default

Optional default value (an R scalar: character, numeric, logical, Date, or POSIXct). In DuckLake the default applies to existing rows as well as future inserts, so the new column appears filled everywhere. Without a default, the column reads NA for existing rows.

Value

Invisibly returns NULL.

See also

drop_table_column(), rename_table_column(), set_column_type(), rename_ducklake_table()

Other schema evolution: drop_table_column(), rename_ducklake_table(), rename_table_column(), set_column_type()

Examples

if (FALSE) { # \dontrun{
add_table_column("adsl", "AGECAT", "VARCHAR")
add_table_column("sales", "discount", "DECIMAL(5,2)", default = 0)
} # }