Concatenate tables by rows.
unionall(sources, env = parent.frame())
list of relop trees or list of data.frames
environment to look to.
order_by node or altered data.frame.
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(AUC = 0.6, R2 = 0.2))
optree <- unionall(list(d, d, d))
cat(format(optree))
sql <- to_sql(optree, my_db, limit = 2)
cat(sql)
print(DBI::dbGetQuery(my_db, sql))
DBI::dbDisconnect(my_db)
}
#> unionall(.,
#> mk_td("d", c(
#> "AUC",
#> "R2")),
#> mk_td("d", c(
#> "AUC",
#> "R2")),
#> mk_td("d", c(
#> "AUC",
#> "R2")))
#> SELECT `AUC`, `R2` FROM ( SELECT
#> `AUC`,
#> `R2`
#> FROM
#> `d` LIMIT 2 ) tsql_15332742917516834563_0000000000 UNION ALL SELECT `AUC`, `R2` FROM ( SELECT
#> `AUC`,
#> `R2`
#> FROM
#> `d` LIMIT 2 ) tsql_15332742917516834563_0000000001 UNION ALL SELECT `AUC`, `R2` FROM ( SELECT
#> `AUC`,
#> `R2`
#> FROM
#> `d` LIMIT 2 ) tsql_15332742917516834563_0000000002 LIMIT 2
#> AUC R2
#> 1 0.6 0.2
#> 2 0.6 0.2