extract_map_data: Extract MAP Keys and Values

In Rduckhts: 'DuckDB' High Throughput Sequencing File Formats Reader Extension

Extract MAP Keys and Values

Description

Helper function to work with DuckDB MAP data (returned as data frames). Can extract keys, values, or search for specific key-value pairs.

Usage

extract_map_data(map_col, operation = "keys", default = NA)

Arguments

map_col	A data frame column from DuckDB MAP data
operation	What to extract: "keys", "values", or a specific key name
default	Default value if key is not found (only used when operation is a key name)

Value

Extracted data based on the operation

Examples

library(DBI)
library(duckdb)

con <- rduckhts_connect()
gff_path <- system.file("extdata", "gff_file.gff.gz", package = "Rduckhts")
rduckhts_gff(con, "annotations", gff_path, attributes_map = TRUE, overwrite = TRUE)
data <- dbGetQuery(con, "SELECT attributes FROM annotations LIMIT 5")
keys <- extract_map_data(data$attributes, "keys")
name_values <- extract_map_data(data$attributes, "Name")
dbDisconnect(con, shutdown = TRUE)

Rduckhts documentation built on Oct. 25, 2026, 1:08 a.m.