Function libduckdb_sys::duckdb_value_varchar

pub unsafe extern "C" fn duckdb_value_varchar(
    result: *mut duckdb_result, 
    col: idx_t, 
    row: idx_t
) -> *mut c_char

returns: The char* value at the specified location, or nullptr if the value cannot be converted. The result must be freed with duckdb_free.