diff --git a/activerecord/CHANGELOG.md b/activerecord/CHANGELOG.md index 554bec17d6..db8fc0e6b8 100644 --- a/activerecord/CHANGELOG.md +++ b/activerecord/CHANGELOG.md @@ -1,3 +1,7 @@ +* Add `#views` and `#view_exists?` methods on connection adapters. + + *Ryuta Kamizono* + * Correct query for PostgreSQL 8.2 compatibility. *Ben Murphy*, *Matthew Draper* diff --git a/activerecord/lib/active_record/connection_adapters/abstract/schema_statements.rb b/activerecord/lib/active_record/connection_adapters/abstract/schema_statements.rb index 08803303cf..43512c6bcc 100644 --- a/activerecord/lib/active_record/connection_adapters/abstract/schema_statements.rb +++ b/activerecord/lib/active_record/connection_adapters/abstract/schema_statements.rb @@ -36,6 +36,19 @@ module ActiveRecord tables.include?(table_name.to_s) end + # Returns an array of view names defined in the database. + def views + raise NotImplementedError, "#views is not implemented" + end + + # Checks to see if the view +view_name+ exists on the database. + # + # view_exists?(:ebooks) + # + def view_exists?(view_name) + views.include?(view_name.to_s) + end + # Returns an array of indexes for the given table. # def indexes(table_name, name = nil) end diff --git a/activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb b/activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb index 597f0d0597..9bb1b0c124 100644 --- a/activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb +++ b/activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb @@ -549,6 +549,22 @@ module ActiveRecord tables(nil, schema, table).any? end + def views # :nodoc: + select_values("SHOW FULL TABLES WHERE table_type = 'VIEW'", 'SCHEMA') + end + + def view_exists?(view_name) # :nodoc: + return false unless view_name.present? + + schema, name = view_name.to_s.split('.', 2) + schema, name = @config[:database], schema unless name # A view was provided without a schema + + sql = "SELECT table_name FROM information_schema.tables WHERE table_type = 'VIEW'" + sql << " AND table_schema = #{quote(schema)} AND table_name = #{quote(name)}" + + select_values(sql, 'SCHEMA').any? + end + # Returns an array of indexes for the given table. def indexes(table_name, name = nil) #:nodoc: indexes = [] diff --git a/activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb b/activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb index 69aa02ccf4..777b5ca95f 100644 --- a/activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb +++ b/activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb @@ -90,6 +90,30 @@ module ActiveRecord SQL end + def views # :nodoc: + select_values(<<-SQL, 'SCHEMA') + SELECT c.relname + FROM pg_class c + LEFT JOIN pg_namespace n ON n.oid = c.relnamespace + WHERE c.relkind IN ('v','m') -- (v)iew, (m)aterialized view + AND n.nspname = ANY (current_schemas(false)) + SQL + end + + def view_exists?(view_name) # :nodoc: + name = Utils.extract_schema_qualified_name(view_name.to_s) + return false unless name.identifier + + select_values(<<-SQL, 'SCHEMA').any? + SELECT c.relname + FROM pg_class c + LEFT JOIN pg_namespace n ON n.oid = c.relnamespace + WHERE c.relkind IN ('v','m') -- (v)iew, (m)aterialized view + AND c.relname = '#{name.identifier}' + AND n.nspname = #{name.schema ? "'#{name.schema}'" : 'ANY (current_schemas(false))'} + SQL + end + def drop_table(table_name, options = {}) # :nodoc: execute "DROP TABLE#{' IF EXISTS' if options[:if_exists]} #{quote_table_name(table_name)}#{' CASCADE' if options[:force] == :cascade}" end diff --git a/activerecord/lib/active_record/connection_adapters/sqlite3_adapter.rb b/activerecord/lib/active_record/connection_adapters/sqlite3_adapter.rb index 24fc67938d..fa7285dca4 100644 --- a/activerecord/lib/active_record/connection_adapters/sqlite3_adapter.rb +++ b/activerecord/lib/active_record/connection_adapters/sqlite3_adapter.rb @@ -325,6 +325,19 @@ module ActiveRecord table_name && tables(nil, table_name).any? end + def views # :nodoc: + select_values("SELECT name FROM sqlite_master WHERE type = 'view' AND name <> 'sqlite_sequence'", 'SCHEMA') + end + + def view_exists?(view_name) # :nodoc: + return false unless view_name.present? + + sql = "SELECT name FROM sqlite_master WHERE type = 'view' AND name <> 'sqlite_sequence'" + sql << " AND name = #{quote(view_name)}" + + select_values(sql, 'SCHEMA').any? + end + # Returns an array of +Column+ objects for the table specified by +table_name+. def columns(table_name) #:nodoc: table_structure(table_name).map do |field| diff --git a/activerecord/test/cases/view_test.rb b/activerecord/test/cases/view_test.rb index 1eb1430065..43785874b0 100644 --- a/activerecord/test/cases/view_test.rb +++ b/activerecord/test/cases/view_test.rb @@ -31,6 +31,15 @@ module ViewBehavior assert_equal ["Ruby for Rails"], books.map(&:name) end + def test_views + assert_equal [Ebook.table_name], @connection.views + end + + def test_view_exists + view_name = Ebook.table_name + assert @connection.view_exists?(view_name), "'#{view_name}' view should exist" + end + def test_table_exists view_name = Ebook.table_name assert @connection.table_exists?(view_name), "'#{view_name}' table should exist" @@ -91,6 +100,15 @@ class ViewWithoutPrimaryKeyTest < ActiveRecord::TestCase assert_equal ["Agile Web Development with Rails"], books.map(&:name) end + def test_views + assert_equal [Paperback.table_name], @connection.views + end + + def test_view_exists + view_name = Paperback.table_name + assert @connection.view_exists?(view_name), "'#{view_name}' view should exist" + end + def test_table_exists view_name = Paperback.table_name assert @connection.table_exists?(view_name), "'#{view_name}' table should exist"