#' spec_result_send_statement
#' @family result specifications
#' @usage NULL
#' @format NULL
#' @keywords NULL
spec_result_send_statement <- list(
send_statement_formals = function() {
# <establish formals of described functions>
expect_equal(names(formals(dbSendStatement)), c("conn", "statement", "..."))
},
send_statement_trivial = function(ctx, con, table_name) {
#' @return
#' `dbSendStatement()` returns
res <- expect_visible(dbSendStatement(con, trivial_statement(ctx, table_name)))
#' an S4 object that inherits from [DBIResult-class].
expect_s4_class(res, "DBIResult")
#' The result set can be used with [dbGetRowsAffected()] to
#' determine the number of rows affected by the query.
expect_error(dbGetRowsAffected(res), NA)
#' Once you have finished using a result, make sure to clear it
#' with [dbClearResult()].
dbClearResult(res)
},
#'
send_statement_closed_connection = function(ctx, closed_con) {
#' @section Failure modes:
#' An error is raised when issuing a statement over a closed
table_name <- "dbit10"
expect_error(dbSendStatement(closed_con, trivial_statement(ctx, table_name = table_name)))
},
send_statement_invalid_connection = function(ctx, invalid_con) {
#' or invalid connection,
table_name <- "dbit11"
expect_error(dbSendStatement(invalid_con, trivial_statement(ctx, table_name = table_name)))
},
send_statement_non_string = function(con) {
#' or if the statement is not a non-`NA` string.
expect_error(dbSendStatement(con, character()))
expect_error(dbSendStatement(con, letters))
expect_error(dbSendStatement(con, NA_character_))
},
send_statement_syntax_error = function(con) {
#' An error is also raised if the syntax of the query is invalid
#' and all query parameters are given (by passing the `params` argument)
#' or the `immediate` argument is set to `TRUE`.
#'
#' @section Failure modes:
expect_error(dbSendStatement(con, "CREATTE", params = list()))
expect_error(dbSendStatement(con, "CREATTE", immediate = TRUE))
},
send_statement_result_valid = function(ctx, con, table_name) {
#' @section Specification:
#' No warnings occur under normal conditions.
expect_warning(res <- dbSendStatement(con, trivial_statement(ctx, table_name)), NA)
#' When done, the DBIResult object must be cleared with a call to
#' [dbClearResult()].
dbClearResult(res)
},
#
send_statement_stale_warning = function(ctx) {
#' Failure to clear the result set leads to a warning
#' when the connection is closed.
con <- connect(ctx)
on.exit(dbDisconnect(con))
expect_warning(dbSendStatement(con, trivial_query()), NA)
expect_warning({
dbDisconnect(con)
gc()
})
on.exit(NULL)
},
send_statement_only_one_result_set = function(ctx, con, table_name) {
#' If the backend supports only one open result set per connection,
res1 <- dbSendStatement(con, trivial_statement(ctx, table_name))
other_table_name <- random_table_name()
local_remove_test_table(con, other_table_name)
#' issuing a second query invalidates an already open result set
#' and raises a warning.
query <- ctx$tweaks$create_table_as(other_table_name, "SELECT 1 AS a")
expect_warning(res2 <- dbSendStatement(con, query))
expect_false(dbIsValid(res1))
#' The newly opened result set is valid
expect_true(dbIsValid(res2))
#' and must be cleared with `dbClearResult()`.
dbClearResult(res2)
},
#' @section Additional arguments:
#' The following arguments are not part of the `dbSendStatement()` generic
#' (to improve compatibility across backends)
#' but are part of the DBI specification:
#' - `params` (default: `NULL`)
#' - `immediate` (default: `NULL`)
#'
#' They must be provided as named arguments.
#' See the "Specification" sections for details on their usage.
send_statement_params = function(ctx, con) {
#' @section Specification:
#'
#' The `param` argument allows passing query parameters, see [dbBind()] for details.
placeholder_funs <- get_placeholder_funs(ctx)
for (placeholder_fun in placeholder_funs) {
table_name <- random_table_name()
local_remove_test_table(con, table_name)
dbWriteTable(con, table_name, data.frame(a = as.numeric(1:3)))
placeholder <- placeholder_fun(1)
query <- paste0("DELETE FROM ", table_name, " WHERE a > ", placeholder)
values <- 1.5
params <- stats::setNames(list(values), names(placeholder))
rs <- dbSendStatement(con, query, params = params)
rc <- dbGetRowsAffected(rs)
if (isTRUE(ctx$tweaks$allow_na_rows_affected)) {
expect_true((is.na(rc) && is.numeric(rc)) || rc == 2L, info = placeholder)
} else {
expect_equal(rc, 2L, info = placeholder)
}
dbClearResult(rs)
}
},
send_statement_immediate = function(ctx, con, table_name) {
#' @inheritSection spec_result_get_query Specification for the `immediate` argument
res <- expect_visible(dbSendStatement(con, trivial_statement(ctx, table_name), immediate = TRUE))
expect_s4_class(res, "DBIResult")
expect_error(dbGetRowsAffected(res), NA)
dbClearResult(res)
},
#
NULL
)
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