saveDF: Save Save a dataframe to a database, storing it in decomposed...

In eccc-cdo/SQLTypeR: Preserve R types in SQL

Description

Save Save a dataframe to a database, storing it in decomposed form:

• a named table with a dumbed-down version of the dataframe, where logicals are coerced to integers, and factors are coerced to strings.

• a metadata table called __types, with the information necessary to recover the logicals and factors in the original dataframe. Additional arguments are passed to the database write call for the data table. The dataframe can be retrieved from the database using loadDF().

Usage

saveDF(con, df, name, overwrite = TRUE, ...)

Arguments

con	An SQL database connection (generated via DBI::dbConnect()).
df	The dataframe to save.
name	The table name to use in the database.
overwrite	Should the dataframe overwrite the existing content under that table name?
...	Additional arguments to pass to the database write call for the dataframe.

See Also

Pure functions to decompose/recompose dataframes: decomposeDF() recomposeDF()

Examples

con <- DBI::dbConnect(RSQLite::SQLite(), ":memory:")

df <- tibble::tibble(
  a = factor(c("a", "a", "b"), levels = c("a", "b"), ordered = TRUE),
  b = c(TRUE, TRUE, FALSE),
  c = c(1,2,3)
 )

saveDF(con, df, "test_1")

loadDF(con, "test_1")

DBI::dbDisconnect(con)

eccc-cdo/SQLTypeR documentation built on March 23, 2020, 5:25 a.m.