Safely disconnect from data and free memory

This function is to ensure that DuckDB connections to CSV.gz files (created via spod_get()), as well as to DuckDB files or folders of parquet files (created via spod_convert()) are closed properly to prevent conflicting connections. Essentially this is just a wrapper around DBI::dbDisconnect() that reaches out into the .$src$con object of the tbl_duckdb_connection connection object that is returned to the user via spod_get() and spod_connect(). After disonnecting the database, it also frees up memory by running gc().

Usage

spod_disconnect(tbl_con, free_mem = TRUE)

Arguments

tbl_con

A tbl_duckdb_connection connection object that you get from either spod_get() or spod_connect().

free_mem

A logical. Whether to free up memory by running gc(). Defaults to TRUE.

Value

No return value, called for side effect of disconnecting from the database and freeing up memory.

Examples

if (FALSE) { # interactive()
# \donttest{
# Set data dir for file downloads
spod_set_data_dir(tempdir())

# basic example
# create a connection to the v1 data without converting
# this creates a duckdb database connection to CSV files
od_distr <- spod_get(
 "od",
 zones = "distr",
 dates = c("2020-03-01", "2020-03-02")
)
# disconnect from the database connection
spod_disconnect(od_distr)

# Advanced example
# download and convert data
dates_1 <- c(start = "2020-02-17", end = "2020-02-19")
db_2 <- spod_convert(
 type = "od",
 zones = "distr",
 dates = dates_1,
 overwrite = TRUE
)

# now connect to the converted data
my_od_data_2 <- spod_connect(db_2)

# disconnect from the database
spod_disconnect(my_od_data_2)
# }
}