# Convert table transforms into nodes (that do not have toSQL() method).
#' Wrap a non-SQL node.
#'
#' Note: non-SQL nodes are allowed to delete/overwrite both
#' both the incoming and outgoing tables, so do not point them
#' to non-temporary structures. Also they tend to land all columns
#' (losing narrowing optimization),
#' so can be expensive and should be used sparingly. Finally their
#' result can only be used once in a pipeline (else they will try to clobber their own result).
#'
#' @param source source to work from (data.frame or relop node)
#' @param ... force later arguments to bind by name
#' @param f_db database implementation signature: f_db(db, incoming_table_name, outgoing_table_name, nd, ...) (db being a database handle)
#' @param f_df data.frame implementation signature: f_df(data.frame, nd) (NULL defaults to taking from database).
#' @param f_dt data.table implementation signature: f_dt(data.table, nd) (NULL defaults f_df).
#' @param incoming_table_name character, name of incoming table
#' @param incoming_qualifiers optional named ordered vector of strings carrying additional db hierarchy terms, such as schema.
#' @param outgoing_table_name character, name of produced table
#' @param outgoing_qualifiers optional named ordered vector of strings carrying additional db hierarchy terms, such as schema.
#' @param columns_produced character, names of additional columns produced
#' @param display_form character, how to print node
#' @param orig_columns logical if TRUE select all original columns.
#' @param temporary logical, if TRUE mark tables temporary.
#' @param check_result_details logical, if TRUE enforce result type and columns.
#' @param env environment to look to.
#' @return non-sql node.
#'
#' @seealso \code{\link{rsummary_node}}, \code{\link{quantile_node}}
#'
#' @export
#'
non_sql_node <- function(source,
...,
f_db = NULL,
f_df = NULL,
f_dt = NULL,
incoming_table_name,
incoming_qualifiers = NULL,
outgoing_table_name,
outgoing_qualifiers = NULL,
columns_produced,
display_form = 'non_sql_node',
orig_columns = TRUE,
temporary = TRUE,
check_result_details = TRUE,
env = parent.frame()) {
wrapr::stop_if_dot_args(substitute(list(...)), "non_sql_node")
force(env)
UseMethod("non_sql_node", source)
}
#' @export
non_sql_node.relop <- function(source,
...,
f_db = NULL,
f_df = NULL,
f_dt = NULL,
incoming_table_name,
incoming_qualifiers = NULL,
outgoing_table_name,
outgoing_qualifiers = NULL,
columns_produced,
display_form = 'non_sql_node',
orig_columns = TRUE,
temporary = TRUE,
check_result_details = TRUE,
env = parent.frame()) {
wrapr::stop_if_dot_args(substitute(list(...)), "non_sql_node.relop")
force(env)
if(is.null(f_db)) {
if(incoming_table_name!=outgoing_table_name) {
stop("non_sql_node.relop: must have incoming_table_name==outgoing_table_name when f_db is NULL")
}
} else {
if(incoming_table_name==outgoing_table_name) {
stop("non_sql_node.relop: must have incoming_table_name!=outgoing_table_name when f_db is not NULL")
}
}
src_cols <- column_names(source)
r <- list(source = list(source),
table_name = outgoing_table_name,
f_db = f_db,
f_df = f_df,
f_dt = f_dt,
incoming_table_name = incoming_table_name,
incoming_qualifiers = incoming_qualifiers,
outgoing_table_name = outgoing_table_name,
outgoing_qualifiers = outgoing_qualifiers,
columns_produced = columns_produced,
display_form = display_form,
orig_columns = orig_columns,
overwrite = TRUE,
src_cols = src_cols,
temporary = temporary,
check_result_details = check_result_details,
allow_narrowing = (length(columns_produced)==0) && orig_columns)
r <- relop_decorate("relop_non_sql", r)
r
}
#' @export
non_sql_node.data.frame <- function(source,
...,
f_db = NULL,
f_df = NULL,
f_dt = NULL,
incoming_table_name,
incoming_qualifiers = NULL,
outgoing_table_name,
outgoing_qualifiers = NULL,
columns_produced,
display_form = 'non_sql_node',
orig_columns = TRUE,
temporary = TRUE,
check_result_details = TRUE,
env = parent.frame()) {
wrapr::stop_if_dot_args(substitute(list(...)), "non_sql_node.data.frame")
force(env)
tmp_name <- mk_tmp_name_source("rquery_tmp")()
dnode <- mk_td(tmp_name, colnames(source))
enode <- non_sql_node(dnode,
f_db = f_db,
f_df = f_df,
f_dt = f_dt,
incoming_table_name = incoming_table_name,
incoming_qualifiers = incoming_qualifiers,
outgoing_table_name = outgoing_table_name,
outgoing_qualifiers = outgoing_qualifiers,
columns_produced = columns_produced,
display_form = display_form,
orig_columns = orig_columns,
temporary = temporary,
check_result_details = check_result_details,
env = env)
rquery_apply_to_data_frame(source, enode, env = env)
}
#' @export
column_names.relop_non_sql <- function (x, ...) {
wrapr::stop_if_dot_args(substitute(list(...)), "column_names.relop_non_sql")
nms <- x$columns_produced
if(x$orig_columns) {
nms <- c(nms, setdiff(column_names(x$source[[1]]), nms))
}
nms
}
#' @export
format_node.relop_non_sql <- function(node) {
paste0("non_sql_node(., ", node$display_form, ")\n")
}
#' @export
columns_used.relop_non_sql <- function (x, ...,
using = NULL) {
if(!x$allow_narrowing) {
using <- NULL
}
columns_used(x$source[[1]],
using = using)
}
#' @export
to_sql.relop_non_sql <- function (x,
db,
...,
limit = NULL,
source_limit = NULL,
indent_level = 0,
tnum = mk_tmp_name_source('tsql'),
append_cr = TRUE,
using = NULL) {
wrapr::stop_if_dot_args(substitute(list(...)), "rquery::to_sql.relop_non_sql")
dispatch_to_sql_method(
method_name = "to_sql.relop_non_sql",
x = x,
db = db,
limit = limit,
source_limit = source_limit,
indent_level = indent_level,
tnum = tnum,
append_cr = append_cr,
using = using)
}
to_sql_relop_non_sql <- function(
x,
db,
...,
limit = NULL,
source_limit = NULL,
indent_level = 0,
tnum = mk_tmp_name_source('tsql'),
append_cr = TRUE,
using = NULL) {
if(!x$allow_narrowing) {
using <- NULL
}
subsql <- to_sql(x$source[[1]],
db = db,
source_limit = source_limit,
indent_level = indent_level + 1,
tnum = tnum,
append_cr = append_cr,
using = using)
nsubsql <- length(subsql)
# non-SQL nodes must always be surrounded by SQL on both sides
step1 <- materialize_sql_statement(db,
subsql[[nsubsql]],
x$incoming_table_name,
qualifiers = x$incoming_qualifiers,
temporary = x$temporary)
nsql_step <- list(display_form = x$display_form,
incoming_table_name = x$incoming_table_name,
incoming_qualifiers = x$incoming_qualifiers,
outgoing_table_name = x$outgoing_table_name,
outgoing_qualifiers = x$outgoing_qualifiers,
temporary = x$temporary,
node = x,
f = x$f_db)
class(nsql_step) <- "rquery_non_sql_step"
step2 <- list(nsql_step)
qlimit = limit
if(!getDBOption(db, "use_pass_limit", TRUE)) {
qlimit = NULL
}
step3 <- list(to_sql(mk_td(x$outgoing_table_name, column_names(x)),
db = db,
limit = qlimit,
source_limit = source_limit,
indent_level = indent_level + 1,
tnum = tnum,
append_cr = append_cr,
using = using))
c(subsql[-length(subsql)], step1, step2, step3)
}
#' @export
format.rquery_non_sql_step <- function(x, ...) {
paste("non SQL step: ", x$display_form)
}
#' @export
print.rquery_non_sql_step <- function(x, ...) {
print(format(x))
}
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