# NOT RUN {
if (requireNamespace("DBI", quietly = TRUE) && requireNamespace("RSQLite", quietly = TRUE)) {
my_db <- DBI::dbConnect(RSQLite::SQLite(),
":memory:")
d <- rq_copy_to(my_db, 'd',
data.frame(a = c("1", "2", "1", "3"),
b = c("1", "1", "3", "2"),
c = c("1", "2", "3", "4"),
stringsAsFactors = FALSE),
temporary = TRUE,
overwrite = TRUE)
mp <- build_frame(
"column_name", "old_value", "new_value" |
"a" , "1" , "10" |
"a" , "2" , "20" |
"b" , "1" , "100" |
"b" , "3" , "300" )
# example
op_tree <- d %.>%
map_column_values(., mp)
cat(format(op_tree))
sql <- to_sql(op_tree, my_db)
cat(sql)
print(DBI::dbGetQuery(my_db, sql))
# cleanup
DBI::dbDisconnect(my_db)
}
# }
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