diff options
Diffstat (limited to 'activerecord/lib/active_record/connection_adapters/sqlite3_adapter.rb')
-rw-r--r-- | activerecord/lib/active_record/connection_adapters/sqlite3_adapter.rb | 580 |
1 files changed, 566 insertions, 14 deletions
diff --git a/activerecord/lib/active_record/connection_adapters/sqlite3_adapter.rb b/activerecord/lib/active_record/connection_adapters/sqlite3_adapter.rb index 0a0da0b5d3..d4ffa82b17 100644 --- a/activerecord/lib/active_record/connection_adapters/sqlite3_adapter.rb +++ b/activerecord/lib/active_record/connection_adapters/sqlite3_adapter.rb @@ -1,12 +1,14 @@ -require 'active_record/connection_adapters/sqlite_adapter' +require 'active_record/connection_adapters/abstract_adapter' +require 'active_record/connection_adapters/statement_pool' +require 'arel/visitors/bind_visitor' -gem 'sqlite3', '~> 1.3.4' +gem 'sqlite3', '~> 1.3.6' require 'sqlite3' module ActiveRecord - class Base + module ConnectionHandling # sqlite3 adapter reuses sqlite_connection. - def self.sqlite3_connection(config) # :nodoc: + def sqlite3_connection(config) # :nodoc: # Require database. unless config[:database] raise ArgumentError, "No database file specified. Missing argument: database" @@ -19,10 +21,6 @@ module ActiveRecord config[:database] = File.expand_path(config[:database], Rails.root) end - unless 'sqlite3' == config[:adapter] - raise ArgumentError, 'adapter name should be "sqlite3"' - end - db = SQLite3::Database.new( config[:database], :results_as_hash => true @@ -35,7 +33,184 @@ module ActiveRecord end module ConnectionAdapters #:nodoc: - class SQLite3Adapter < SQLiteAdapter # :nodoc: + class SQLite3Column < Column #:nodoc: + class << self + def binary_to_string(value) + if value.encoding != Encoding::ASCII_8BIT + value = value.force_encoding(Encoding::ASCII_8BIT) + end + value + end + end + end + + # The SQLite3 adapter works SQLite 3.6.16 or newer + # with the sqlite3-ruby drivers (available as gem from https://rubygems.org/gems/sqlite3). + # + # Options: + # + # * <tt>:database</tt> - Path to the database file. + class SQLite3Adapter < AbstractAdapter + class Version + include Comparable + + def initialize(version_string) + @version = version_string.split('.').map { |v| v.to_i } + end + + def <=>(version_string) + @version <=> version_string.split('.').map { |v| v.to_i } + end + end + + class StatementPool < ConnectionAdapters::StatementPool + def initialize(connection, max) + super + @cache = Hash.new { |h,pid| h[pid] = {} } + end + + def each(&block); cache.each(&block); end + def key?(key); cache.key?(key); end + def [](key); cache[key]; end + def length; cache.length; end + + def []=(sql, key) + while @max <= cache.size + dealloc(cache.shift.last[:stmt]) + end + cache[sql] = key + end + + def clear + cache.values.each do |hash| + dealloc hash[:stmt] + end + cache.clear + end + + private + def cache + @cache[$$] + end + + def dealloc(stmt) + stmt.close unless stmt.closed? + end + end + + class BindSubstitution < Arel::Visitors::SQLite # :nodoc: + include Arel::Visitors::BindVisitor + end + + def initialize(connection, logger, config) + super(connection, logger) + @statements = StatementPool.new(@connection, + config.fetch(:statement_limit) { 1000 }) + @config = config + + if config.fetch(:prepared_statements) { true } + @visitor = Arel::Visitors::SQLite.new self + else + @visitor = BindSubstitution.new self + end + end + + def adapter_name #:nodoc: + 'SQLite' + end + + # Returns true + def supports_ddl_transactions? + true + end + + # Returns true if SQLite version is '3.6.8' or greater, false otherwise. + def supports_savepoints? + sqlite_version >= '3.6.8' + end + + # Returns true, since this connection adapter supports prepared statement + # caching. + def supports_statement_cache? + true + end + + # Returns true, since this connection adapter supports migrations. + def supports_migrations? #:nodoc: + true + end + + # Returns true. + def supports_primary_key? #:nodoc: + true + end + + def requires_reloading? + true + end + + # Returns true + def supports_add_column? + true + end + + # Disconnects from the database if already connected. Otherwise, this + # method does nothing. + def disconnect! + super + clear_cache! + @connection.close rescue nil + end + + # Clears the prepared statements cache. + def clear_cache! + @statements.clear + end + + # Returns true + def supports_count_distinct? #:nodoc: + true + end + + # Returns true + def supports_autoincrement? #:nodoc: + true + end + + def supports_index_sort_order? + true + end + + def native_database_types #:nodoc: + { + :primary_key => default_primary_key_type, + :string => { :name => "varchar", :limit => 255 }, + :text => { :name => "text" }, + :integer => { :name => "integer" }, + :float => { :name => "float" }, + :decimal => { :name => "decimal" }, + :datetime => { :name => "datetime" }, + :timestamp => { :name => "datetime" }, + :time => { :name => "datetime" }, + :date => { :name => "date" }, + :binary => { :name => "blob" }, + :boolean => { :name => "boolean" } + } + end + + # Returns the current database encoding format as a string, eg: 'UTF-8' + def encoding + @connection.encoding.to_s + end + + # Returns true. + def supports_explain? + true + end + + + # QUOTING ================================================== + def quote(value, column = nil) if value.kind_of?(String) && column && column.type == :binary && column.class.respond_to?(:string_to_binary) s = column.class.string_to_binary(value).unpack("H*")[0] @@ -45,15 +220,392 @@ module ActiveRecord end end - # Returns the current database encoding format as a string, eg: 'UTF-8' - def encoding - if @connection.respond_to?(:encoding) - @connection.encoding.to_s + + def quote_string(s) #:nodoc: + @connection.class.quote(s) + end + + def quote_column_name(name) #:nodoc: + %Q("#{name.to_s.gsub('"', '""')}") + end + + # Quote date/time values for use in SQL input. Includes microseconds + # if the value is a Time responding to usec. + def quoted_date(value) #:nodoc: + if value.respond_to?(:usec) + "#{super}.#{sprintf("%06d", value.usec)}" else - @connection.execute('PRAGMA encoding')[0]['encoding'] + super + end + end + + def type_cast(value, column) # :nodoc: + return value.to_f if BigDecimal === value + return super unless String === value + return super unless column && value + + value = super + if column.type == :string && value.encoding == Encoding::ASCII_8BIT + logger.error "Binary data inserted for `string` type on column `#{column.name}`" if logger + value.encode! 'utf-8' end + value + end + + # DATABASE STATEMENTS ====================================== + + def explain(arel, binds = []) + sql = "EXPLAIN QUERY PLAN #{to_sql(arel, binds)}" + ExplainPrettyPrinter.new.pp(exec_query(sql, 'EXPLAIN', binds)) end + class ExplainPrettyPrinter + # Pretty prints the result of a EXPLAIN QUERY PLAN in a way that resembles + # the output of the SQLite shell: + # + # 0|0|0|SEARCH TABLE users USING INTEGER PRIMARY KEY (rowid=?) (~1 rows) + # 0|1|1|SCAN TABLE posts (~100000 rows) + # + def pp(result) # :nodoc: + result.rows.map do |row| + row.join('|') + end.join("\n") + "\n" + end + end + + def exec_query(sql, name = nil, binds = []) + log(sql, name, binds) do + + # Don't cache statements without bind values + if binds.empty? + stmt = @connection.prepare(sql) + cols = stmt.columns + records = stmt.to_a + stmt.close + stmt = records + else + cache = @statements[sql] ||= { + :stmt => @connection.prepare(sql) + } + stmt = cache[:stmt] + cols = cache[:cols] ||= stmt.columns + stmt.reset! + stmt.bind_params binds.map { |col, val| + type_cast(val, col) + } + end + + ActiveRecord::Result.new(cols, stmt.to_a) + end + end + + def exec_delete(sql, name = 'SQL', binds = []) + exec_query(sql, name, binds) + @connection.changes + end + alias :exec_update :exec_delete + + def last_inserted_id(result) + @connection.last_insert_row_id + end + + def execute(sql, name = nil) #:nodoc: + log(sql, name) { @connection.execute(sql) } + end + + def update_sql(sql, name = nil) #:nodoc: + super + @connection.changes + end + + def delete_sql(sql, name = nil) #:nodoc: + sql += " WHERE 1=1" unless sql =~ /WHERE/i + super sql, name + end + + def insert_sql(sql, name = nil, pk = nil, id_value = nil, sequence_name = nil) #:nodoc: + super + id_value || @connection.last_insert_row_id + end + alias :create :insert_sql + + def select_rows(sql, name = nil) + exec_query(sql, name).rows + end + + def create_savepoint + execute("SAVEPOINT #{current_savepoint_name}") + end + + def rollback_to_savepoint + execute("ROLLBACK TO SAVEPOINT #{current_savepoint_name}") + end + + def release_savepoint + execute("RELEASE SAVEPOINT #{current_savepoint_name}") + end + + def begin_db_transaction #:nodoc: + log('begin transaction',nil) { @connection.transaction } + end + + def commit_db_transaction #:nodoc: + log('commit transaction',nil) { @connection.commit } + end + + def rollback_db_transaction #:nodoc: + log('rollback transaction',nil) { @connection.rollback } + end + + # SCHEMA STATEMENTS ======================================== + + def tables(name = 'SCHEMA', table_name = nil) #:nodoc: + sql = <<-SQL + SELECT name + FROM sqlite_master + WHERE type = 'table' AND NOT name = 'sqlite_sequence' + SQL + sql << " AND name = #{quote_table_name(table_name)}" if table_name + + exec_query(sql, name).map do |row| + row['name'] + end + end + + def table_exists?(name) + name && tables('SCHEMA', name).any? + end + + # Returns an array of +SQLite3Column+ objects for the table specified by +table_name+. + def columns(table_name) #:nodoc: + table_structure(table_name).map do |field| + case field["dflt_value"] + when /^null$/i + field["dflt_value"] = nil + when /^'(.*)'$/ + field["dflt_value"] = $1.gsub("''", "'") + when /^"(.*)"$/ + field["dflt_value"] = $1.gsub('""', '"') + end + + SQLite3Column.new(field['name'], field['dflt_value'], field['type'], field['notnull'].to_i == 0) + end + end + + # Returns an array of indexes for the given table. + def indexes(table_name, name = nil) #:nodoc: + exec_query("PRAGMA index_list(#{quote_table_name(table_name)})", name).map do |row| + IndexDefinition.new( + table_name, + row['name'], + row['unique'] != 0, + exec_query("PRAGMA index_info('#{row['name']}')").map { |col| + col['name'] + }) + end + end + + def primary_key(table_name) #:nodoc: + column = table_structure(table_name).find { |field| + field['pk'] == 1 + } + column && column['name'] + end + + def remove_index!(table_name, index_name) #:nodoc: + exec_query "DROP INDEX #{quote_column_name(index_name)}" + end + + # Renames a table. + # + # Example: + # rename_table('octopuses', 'octopi') + def rename_table(name, new_name) + exec_query "ALTER TABLE #{quote_table_name(name)} RENAME TO #{quote_table_name(new_name)}" + end + + # See: http://www.sqlite.org/lang_altertable.html + # SQLite has an additional restriction on the ALTER TABLE statement + def valid_alter_table_options( type, options) + type.to_sym != :primary_key + end + + def add_column(table_name, column_name, type, options = {}) #:nodoc: + if supports_add_column? && valid_alter_table_options( type, options ) + super(table_name, column_name, type, options) + else + alter_table(table_name) do |definition| + definition.column(column_name, type, options) + end + end + end + + def remove_column(table_name, *column_names) #:nodoc: + raise ArgumentError.new("You must specify at least one column name. Example: remove_column(:people, :first_name)") if column_names.empty? + column_names.each do |column_name| + alter_table(table_name) do |definition| + definition.columns.delete(definition[column_name]) + end + end + end + alias :remove_columns :remove_column + + def change_column_default(table_name, column_name, default) #:nodoc: + alter_table(table_name) do |definition| + definition[column_name].default = default + end + end + + def change_column_null(table_name, column_name, null, default = nil) + unless null || default.nil? + exec_query("UPDATE #{quote_table_name(table_name)} SET #{quote_column_name(column_name)}=#{quote(default)} WHERE #{quote_column_name(column_name)} IS NULL") + end + alter_table(table_name) do |definition| + definition[column_name].null = null + end + end + + def change_column(table_name, column_name, type, options = {}) #:nodoc: + alter_table(table_name) do |definition| + include_default = options_include_default?(options) + definition[column_name].instance_eval do + self.type = type + self.limit = options[:limit] if options.include?(:limit) + self.default = options[:default] if include_default + self.null = options[:null] if options.include?(:null) + self.precision = options[:precision] if options.include?(:precision) + self.scale = options[:scale] if options.include?(:scale) + end + end + end + + def rename_column(table_name, column_name, new_column_name) #:nodoc: + unless columns(table_name).detect{|c| c.name == column_name.to_s } + raise ActiveRecord::ActiveRecordError, "Missing column #{table_name}.#{column_name}" + end + alter_table(table_name, :rename => {column_name.to_s => new_column_name.to_s}) + end + + def empty_insert_statement_value + "VALUES(NULL)" + end + + protected + def select(sql, name = nil, binds = []) #:nodoc: + exec_query(sql, name, binds) + end + + def table_structure(table_name) + structure = exec_query("PRAGMA table_info(#{quote_table_name(table_name)})", 'SCHEMA').to_hash + raise(ActiveRecord::StatementInvalid, "Could not find table '#{table_name}'") if structure.empty? + structure + end + + def alter_table(table_name, options = {}) #:nodoc: + altered_table_name = "altered_#{table_name}" + caller = lambda {|definition| yield definition if block_given?} + + transaction do + move_table(table_name, altered_table_name, + options.merge(:temporary => true)) + move_table(altered_table_name, table_name, &caller) + end + end + + def move_table(from, to, options = {}, &block) #:nodoc: + copy_table(from, to, options, &block) + drop_table(from) + end + + def copy_table(from, to, options = {}) #:nodoc: + from_primary_key = primary_key(from) + options[:primary_key] = from_primary_key if from_primary_key != 'id' + unless options[:primary_key] + options[:id] = columns(from).detect{|c| c.name == 'id'}.present? && from_primary_key == 'id' + end + create_table(to, options) do |definition| + @definition = definition + columns(from).each do |column| + column_name = options[:rename] ? + (options[:rename][column.name] || + options[:rename][column.name.to_sym] || + column.name) : column.name + + @definition.column(column_name, column.type, + :limit => column.limit, :default => column.default, + :precision => column.precision, :scale => column.scale, + :null => column.null) + end + @definition.primary_key(from_primary_key) if from_primary_key + yield @definition if block_given? + end + + copy_table_indexes(from, to, options[:rename] || {}) + copy_table_contents(from, to, + @definition.columns.map {|column| column.name}, + options[:rename] || {}) + end + + def copy_table_indexes(from, to, rename = {}) #:nodoc: + indexes(from).each do |index| + name = index.name + if to == "altered_#{from}" + name = "temp_#{name}" + elsif from == "altered_#{to}" + name = name[5..-1] + end + + to_column_names = columns(to).map { |c| c.name } + columns = index.columns.map {|c| rename[c] || c }.select do |column| + to_column_names.include?(column) + end + + unless columns.empty? + # index name can't be the same + opts = { :name => name.gsub(/_(#{from})_/, "_#{to}_") } + opts[:unique] = true if index.unique + add_index(to, columns, opts) + end + end + end + + def copy_table_contents(from, to, columns, rename = {}) #:nodoc: + column_mappings = Hash[columns.map {|name| [name, name]}] + rename.each { |a| column_mappings[a.last] = a.first } + from_columns = columns(from).collect {|col| col.name} + columns = columns.find_all{|col| from_columns.include?(column_mappings[col])} + quoted_columns = columns.map { |col| quote_column_name(col) } * ',' + + quoted_to = quote_table_name(to) + exec_query("SELECT * FROM #{quote_table_name(from)}").each do |row| + sql = "INSERT INTO #{quoted_to} (#{quoted_columns}) VALUES (" + sql << columns.map {|col| quote row[column_mappings[col]]} * ', ' + sql << ')' + exec_query sql + end + end + + def sqlite_version + @sqlite_version ||= SQLite3Adapter::Version.new(select_value('select sqlite_version(*)')) + end + + def default_primary_key_type + if supports_autoincrement? + 'INTEGER PRIMARY KEY AUTOINCREMENT NOT NULL' + else + 'INTEGER PRIMARY KEY NOT NULL' + end + end + + def translate_exception(exception, message) + case exception.message + when /column(s)? .* (is|are) not unique/ + RecordNotUnique.new(message, exception) + else + super + end + end + end end end |