loadDF: Load Load a named dataframe from a database, where it is...

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

Description

Load Load a named dataframe from a database, where it is stored 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. The dataframe can be saved back to the database using saveDF().

Usage

loadDF(con, name)

Arguments

con	An SQL database connection (generated via DBI::dbConnect()).
name	The name of the table to load from the database.

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.