Support schema-qualified table names when using create_table :temp wi…

…th a Sequel::SQL::QualifiedIdentifier (Fixes #2185)

1fd3976 stopped supporting this
due to problems when setting default_schema on PostgreSQL.  However,
just using the inspect version of Sequel::SQL::QualifiedIdentifier
as the table name is not something any user wants.  PostgreSQL does
not support schema-qualified temporary tables, and I'm not sure
if any other databases do, but it's better to issue the query with
a schema qualified table and have it raise an error, as opposed
to having it silently succeed with a bogus name.

CHANGELOG

@@ -1,5 +1,7 @@
 === master
 
+* Support schema-qualified table names when using create_table :temp with a Sequel::SQL::QualifiedIdentifier (jeremyevans) (#2185)
+
 * Support MERGE WHEN NOT MATCHED BY SOURCE on PostgreSQL 17+ (jeremyevans)
 
 * Add stdio_logger extension for a minimal logger that Sequel::Database can use (jeremyevans)

lib/sequel/adapters/jdbc/derby.rb

@@ -115,7 +115,7 @@ def create_table_as_sql(name, sql, options)
         # Temporary table creation on Derby uses DECLARE instead of CREATE.
         def create_table_prefix_sql(name, options)
           if options[:temp]
-            "DECLARE GLOBAL TEMPORARY TABLE #{quote_identifier(name)}"
+            "DECLARE GLOBAL TEMPORARY TABLE #{create_table_table_name_sql(name, options)}"
           else
             super
           end

lib/sequel/adapters/shared/db2.rb

@@ -198,7 +198,7 @@ def create_table_as_sql(name, sql, options)
       # http://www.ibm.com/developerworks/data/library/techarticle/dm-0912globaltemptable/
       def create_table_prefix_sql(name, options)
         if options[:temp]
-          "DECLARE GLOBAL TEMPORARY TABLE #{quote_identifier(name)}"
+          "DECLARE GLOBAL TEMPORARY TABLE #{create_table_table_name_sql(name, options)}"
         else
           super
         end

lib/sequel/adapters/shared/mssql.rb

@@ -379,9 +379,21 @@ def commit_transaction_sql
       # a regular and temporary table, with temporary table names starting with
       # a #.
       def create_table_prefix_sql(name, options)
-        "CREATE TABLE #{quote_schema_table(options[:temp] ? "##{name}" : name)}"
+        "CREATE TABLE #{create_table_table_name_sql(name, options)}"
       end
-
+
+      # The SQL to use for the table name for a temporary table.
+      def create_table_temp_table_name_sql(name, _options)
+        case name
+        when String, Symbol
+          "##{name}"
+        when SQL::Identifier
+          "##{name.value}"
+        else
+          raise Error, "temporary table names must be strings, symbols, or Sequel::SQL::Identifier instances on Microsoft SQL Server"
+        end
+      end
+
       # MSSQL doesn't support CREATE TABLE AS, it only supports SELECT INTO.
       # Emulating CREATE TABLE AS using SELECT INTO is only possible if a dataset
       # is given as the argument, it can't work with a string, so raise an

lib/sequel/adapters/shared/postgres.rb

@@ -1429,7 +1429,7 @@ def create_table_prefix_sql(name, options)
           'UNLOGGED '
         end
 
-        "CREATE #{prefix_sql}TABLE#{' IF NOT EXISTS' if options[:if_not_exists]} #{options[:temp] ? quote_identifier(name) : quote_schema_table(name)}"
+        "CREATE #{prefix_sql}TABLE#{' IF NOT EXISTS' if options[:if_not_exists]} #{create_table_table_name_sql(name, options)}"
       end
 
       # SQL for creating a table with PostgreSQL specific options

lib/sequel/database/schema_methods.rb

@@ -775,7 +775,21 @@ def create_table_as_sql(name, sql, options)
 
     # SQL fragment for initial part of CREATE TABLE statement
     def create_table_prefix_sql(name, options)
-      "CREATE #{temporary_table_sql if options[:temp]}TABLE#{' IF NOT EXISTS' if options[:if_not_exists]} #{options[:temp] ? quote_identifier(name) : quote_schema_table(name)}"
+      "CREATE #{temporary_table_sql if options[:temp]}TABLE#{' IF NOT EXISTS' if options[:if_not_exists]} #{create_table_table_name_sql(name, options)}"
+    end
+
+    # The SQL to use for a table name when creating a table.
+    # Use of the :temp option can result in different SQL,
+    # because the rules for temp table naming can differ
+    # between databases, and temp tables should not use the
+    # default_schema.
+    def create_table_table_name_sql(name, options)
+      options[:temp] ? create_table_temp_table_name_sql(name, options) : quote_schema_table(name)
+    end
+
+    # The SQL to use for the table name for a temporary table.
+    def create_table_temp_table_name_sql(name, _options)
+      name.is_a?(String) ? quote_identifier(name) : literal(name)
     end
 
     # SQL fragment for initial part of CREATE VIEW statement

spec/core/schema_spec.rb

@@ -1445,6 +1445,17 @@ def @db.foreign_key_list(table_name)
     @db.sqls.must_equal ['CREATE TEMPORARY TABLE test_tmp (id integer NOT NULL PRIMARY KEY AUTOINCREMENT, name text)',
       'CREATE UNIQUE INDEX test_tmp_name_index ON test_tmp (name)']
   end
+
+  it "should create a schema-qualified temporary table" do
+    @db.create_table Sequel[:sch][:test_tmp], :temp => true do
+      primary_key :id, :integer, :null => false
+      column :name, :text
+      index :name, :unique => true
+    end
+
+    @db.sqls.must_equal ['CREATE TEMPORARY TABLE sch.test_tmp (id integer NOT NULL PRIMARY KEY AUTOINCREMENT, name text)',
+      'CREATE UNIQUE INDEX sch_test_tmp_name_index ON sch.test_tmp (name)']
+  end
 end
 
 describe "Database#alter_table" do

spec/integration/schema_test.rb

@@ -384,13 +384,32 @@
 end if DB.supports_foreign_key_parsing?
 
 describe "Database" do
-  after do
+  before do
     DB.drop_table(:items_temp) rescue nil
   end
-
-  it "should create temporary tables without raising an exception" do
+  after(:all) do
     DB.disconnect
-    DB.create_table!(:items_temp, :temp=>true){Integer :number}
+  end
+
+  it "should allow creation and use of temporary tables" do
+    DB.synchronize do
+      DB.create_table!(:items_temp, :temp=>true){Integer :number}
+      table = case DB.database_type
+      when :mssql
+        Sequel.lit("#items_temp")
+      when :derby
+        Sequel[:session][:items_temp]
+      else
+        :items_temp
+      end
+      DB.from(table).all.must_equal []
+    end
+  end
+
+  it "should raise when trying to create a schema qualified temporary table" do
+    proc do
+      DB.create_table(Sequel[:invalid_temp_schema][:items_temp], :temp=>true){Integer :number}
+    end.must_raise(DB.database_type == :mssql ? Sequel::Error : Sequel::DatabaseError)
   end
 end