spanishoddata (version 0.2.0)

spod_disconnect: Safely disconnect from data and free memory

Description

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)

Value

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

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.

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)
# }
}