Refine table_name_table() interface

R/backend-postgres-old.R

@@ -15,7 +15,6 @@ db_write_table.PostgreSQLConnection <- function(con,
                                                 values,
                                                 temporary = TRUE,
                                                 ...) {
-  table <- as_table_name(table, con)
   if (!isFALSE(temporary)) {
     cli_abort(c(
       "RPostgreSQL backend does not support creation of temporary tables",
@@ -27,7 +26,7 @@ db_write_table.PostgreSQLConnection <- function(con,
   # the bare table name
   dbWriteTable(
     con,
-    name = db_table_name_extract(con, table),
+    name = table_name_table(table, con),
     value = values,
     field.types = types,
     ...,

R/db-sql.R

@@ -176,7 +176,7 @@ sql_table_index.DBIConnection <- function(con,
   table <- as_table_name(table, con)
 
   if (is.null(name)) {
-    table_name <- db_table_name_extract(con, table)
+    table_name <- table_name_table(table, con)
     name <- name %||% paste0(c(table_name, columns), collapse = "_")
   }
   glue_sql2(
@@ -259,7 +259,7 @@ sql_query_wrap.DBIConnection <- function(con, from, name = NULL, ..., lvl = 0) {
     glue_sql2(con, "{from}", as_sql, "{.tbl name}")
   } else { # must be a table_name
     if (!is.null(name)) {
-      table <- db_table_name_extract(con, name)
+      table <- table_name_table(name, con)
       names(from) <- as_table_name(table, con)
     }
     from

R/lazy-join-query.R

@@ -153,6 +153,7 @@ op_vars.lazy_semi_join_query <- function(op) {
 
 #' @export
 sql_build.lazy_multi_join_query <- function(op, con, ..., sql_options = NULL) {
+
   table_names_out <- generate_join_table_names(op$table_names, con)
 
   tables <- set_names(c(list(op$x), op$joins$table), table_names_out)
@@ -188,7 +189,7 @@ sql_build.lazy_multi_join_query <- function(op, con, ..., sql_options = NULL) {
 }
 
 generate_join_table_names <- function(table_names, con) {
-  names <- db_table_name_extract(con, table_names$name)
+  names <- table_name_table(table_names$name, con)
   table_name_length_max <- max(nchar(names))
 
   if (length(table_names$name) != 2) {

R/query-join.R

@@ -331,29 +331,20 @@ sql_join_tbls <- function(con, by, na_matches) {
 }
 
 sql_table_prefix <- function(con, var, table = NULL) {
-
   if (!is_bare_character(var)) {
     cli_abort("{.arg var} must be a bare character.", .internal = TRUE)
   }
   var <- sql_escape_ident(con, var)
-
-  if (!is.null(table)) {
-    table <- as_table_name(table, con)
-    table <- db_table_name_extract(con, table)
-    table <- as_table_name(table, con)
-
-    sql(paste0(table, ".", var))
-  } else {
-    var
-  }
+  sql_table_name_prefix(con, table, var)
 }
 
 sql_star <- function(con, table = NULL) {
-  # TODO: sql_table_prefix(con, "*", table) ?
-  var <- sql("*")
+  sql_table_name_prefix(con, table, sql("*"))
+}
+
+sql_table_name_prefix <- function(con, table, var) {
   if (!is.null(table)) {
-    table <- as_table_name(table, con)
-    table <- db_table_name_extract(con, table)
+    table <- table_name_table(table, con)
     table <- as_table_name(table, con)
 
     sql(paste0(table, ".", var))

R/remote.R

@@ -40,7 +40,7 @@ remote_name <- function(x, null_if_local = TRUE) {
     if (is.null(con)) {
       table
     } else {
-      db_table_name_extract(con, table)
+      table_name_table(table, con)
     }
   }
 }

R/table-name.R

@@ -55,9 +55,20 @@ as_table_names <- function(x, con) {
   make_table_name(x, con, collapse = FALSE)
 }
 
-# TODO: make this generic
-db_parse_table_name <- function(con, x) {
-  quote_char <- substr( sql_escape_ident(con, ""), 1, 1)
+# Extract just the table name from a full identifier
+table_name_table <- function(x, con) {
+  x <- as_table_name(x, con)
+
+  vapply(x, FUN.VALUE = character(1), function(x) {
+    if (x == "") return("")
+
+    out <- table_name_components(x, con)
+    out[[length(out)]]
+  })
+}
+table_name_components <- function(x, con) {
+  quote_char <- substr(sql_escape_ident(con, ""), 1, 1)
+
   scan(
     text = x,
     what = character(),
@@ -67,29 +78,21 @@ db_parse_table_name <- function(con, x) {
     sep = "."
   )
 }
-db_table_name_extract <- function(con, x) {
-  vapply(x, FUN.VALUE = character(1), function(x) {
-    if (x == "") return("")
-
-    out <- db_parse_table_name(con, x)
-    out[[length(out)]]
-  })
-}
 
 #' @export
 escape.dbplyr_table_name <- function(x, parens = FALSE, collapse = ", ", con = NULL) {
-  alias <- names2(x) # assume alias is already escaped
-  x <- unname(x)
-
-  table_name <- as_table_name(db_table_name_extract(con, x), con)
+  # names are always already escaped
+  alias <- names2(x)
+  table_name <- as_table_name(table_name_table(x, con), con)
+  has_alias <- alias == "" | alias == table_name
 
   if (db_supports_table_alias_with_as(con)) {
     as_sql <- style_kw(" AS ")
   } else {
     as_sql <- " "
   }
 
-  out <- ifelse(alias == "" | alias == table_name, x, paste0(x, as_sql, alias))
+  out <- ifelse(has_alias, unname(x), paste0(x, as_sql, alias))
   sql_vector(out, parens, collapse, con = con)
 }
 

R/utils.R

@@ -89,7 +89,7 @@ add_temporary_prefix <- function(con, table, temporary = TRUE) {
     return(table)
   }
 
-  pieces <- db_parse_table_name(con, table)
+  pieces <- table_name_components(table, con)
   table_name <- pieces[length(pieces)]
 
   if (substr(table_name, 1, 1) != "#") {

tests/testthat/test-verb-joins.R

@@ -102,11 +102,11 @@ test_that("alias truncates long table names at database limit", {
   # Source: https://www.postgresql.org/docs/current/sql-syntax-lexical.html#SQL-SYNTAX-IDENTIFIERS
   con <- src_test("postgres")
 
-  nm1 <- paste0("a", paste0(0:61 %% 10, collapse = ""))
-  mf1 <- local_db_table(con, tibble(x = 1:3, y = "a"), nm1)
+  nm1 <- table_name(paste0("a", paste0(0:61 %% 10, collapse = "")))
+  mf1 <- local_db_table(con, tibble(x = 1:3, y = "a"), unclass(nm1))
 
-  nm2 <- paste0("b", paste0(0:61 %% 10, collapse = ""))
-  mf2 <- local_db_table(con, tibble(x = 2:3, y = "b"), nm2)
+  nm2 <- table_name(paste0("b", paste0(0:61 %% 10, collapse = "")))
+  mf2 <- local_db_table(con, tibble(x = 2:3, y = "b"), unclass(nm2))
 
   # 2 tables
   # aliased names are as expected