408 lines
13 KiB
Ruby
408 lines
13 KiB
Ruby
# Author: Luke Holden <lholden@cablelan.net>
|
|
# Updated for SQLite3: Jamis Buck <jamis@37signals.com>
|
|
|
|
require 'active_record/connection_adapters/abstract_adapter'
|
|
|
|
module ActiveRecord
|
|
class Base
|
|
class << self
|
|
# sqlite3 adapter reuses sqlite_connection.
|
|
def sqlite3_connection(config) # :nodoc:
|
|
parse_config!(config)
|
|
|
|
unless self.class.const_defined?(:SQLite3)
|
|
require_library_or_gem(config[:adapter])
|
|
end
|
|
|
|
db = SQLite3::Database.new(
|
|
config[:database],
|
|
:results_as_hash => true,
|
|
:type_translation => false
|
|
)
|
|
|
|
db.busy_timeout(config[:timeout]) unless config[:timeout].nil?
|
|
|
|
ConnectionAdapters::SQLite3Adapter.new(db, logger)
|
|
end
|
|
|
|
# Establishes a connection to the database that's used by all Active Record objects
|
|
def sqlite_connection(config) # :nodoc:
|
|
parse_config!(config)
|
|
|
|
unless self.class.const_defined?(:SQLite)
|
|
require_library_or_gem(config[:adapter])
|
|
|
|
db = SQLite::Database.new(config[:database], 0)
|
|
db.show_datatypes = "ON" if !defined? SQLite::Version
|
|
db.results_as_hash = true if defined? SQLite::Version
|
|
db.type_translation = false
|
|
|
|
# "Downgrade" deprecated sqlite API
|
|
if SQLite.const_defined?(:Version)
|
|
ConnectionAdapters::SQLite2Adapter.new(db, logger)
|
|
else
|
|
ConnectionAdapters::DeprecatedSQLiteAdapter.new(db, logger)
|
|
end
|
|
end
|
|
end
|
|
|
|
private
|
|
def parse_config!(config)
|
|
config[:database] ||= config[:dbfile]
|
|
# Require database.
|
|
unless config[:database]
|
|
raise ArgumentError, "No database file specified. Missing argument: database"
|
|
end
|
|
|
|
# Allow database path relative to RAILS_ROOT, but only if
|
|
# the database path is not the special path that tells
|
|
# Sqlite build a database only in memory.
|
|
if Object.const_defined?(:RAILS_ROOT) && ':memory:' != config[:database]
|
|
config[:database] = File.expand_path(config[:database], RAILS_ROOT)
|
|
end
|
|
end
|
|
end
|
|
end
|
|
|
|
module ConnectionAdapters #:nodoc:
|
|
class SQLiteColumn < Column #:nodoc:
|
|
class << self
|
|
def string_to_binary(value)
|
|
value.gsub(/\0|\%/n) do |b|
|
|
case b
|
|
when "\0" then "%00"
|
|
when "%" then "%25"
|
|
end
|
|
end
|
|
end
|
|
|
|
def binary_to_string(value)
|
|
value.gsub(/%00|%25/n) do |b|
|
|
case b
|
|
when "%00" then "\0"
|
|
when "%25" then "%"
|
|
end
|
|
end
|
|
end
|
|
end
|
|
end
|
|
|
|
# The SQLite adapter works with both the 2.x and 3.x series of SQLite with the sqlite-ruby drivers (available both as gems and
|
|
# from http://rubyforge.org/projects/sqlite-ruby/).
|
|
#
|
|
# Options:
|
|
#
|
|
# * <tt>:database</tt> -- Path to the database file.
|
|
class SQLiteAdapter < AbstractAdapter
|
|
def adapter_name #:nodoc:
|
|
'SQLite'
|
|
end
|
|
|
|
def supports_migrations? #:nodoc:
|
|
true
|
|
end
|
|
|
|
def requires_reloading?
|
|
true
|
|
end
|
|
|
|
def supports_count_distinct? #:nodoc:
|
|
false
|
|
end
|
|
|
|
def native_database_types #:nodoc:
|
|
{
|
|
:primary_key => "INTEGER PRIMARY KEY NOT NULL",
|
|
: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
|
|
|
|
|
|
# QUOTING ==================================================
|
|
|
|
def quote_string(s) #:nodoc:
|
|
@connection.class.quote(s)
|
|
end
|
|
|
|
def quote_column_name(name) #:nodoc:
|
|
%Q("#{name}")
|
|
end
|
|
|
|
|
|
# DATABASE STATEMENTS ======================================
|
|
|
|
def execute(sql, name = nil) #:nodoc:
|
|
catch_schema_changes { log(sql, name) { @connection.execute(sql) } }
|
|
end
|
|
|
|
def update(sql, name = nil) #:nodoc:
|
|
execute(sql, name)
|
|
@connection.changes
|
|
end
|
|
|
|
def delete(sql, name = nil) #:nodoc:
|
|
sql += " WHERE 1=1" unless sql =~ /WHERE/i
|
|
execute(sql, name)
|
|
@connection.changes
|
|
end
|
|
|
|
def insert(sql, name = nil, pk = nil, id_value = nil, sequence_name = nil) #:nodoc:
|
|
execute(sql, name = nil)
|
|
id_value || @connection.last_insert_row_id
|
|
end
|
|
|
|
def select_all(sql, name = nil) #:nodoc:
|
|
execute(sql, name).map do |row|
|
|
record = {}
|
|
row.each_key do |key|
|
|
if key.is_a?(String)
|
|
record[key.sub(/^\w+\./, '')] = row[key]
|
|
end
|
|
end
|
|
record
|
|
end
|
|
end
|
|
|
|
def select_one(sql, name = nil) #:nodoc:
|
|
result = select_all(sql, name)
|
|
result.nil? ? nil : result.first
|
|
end
|
|
|
|
|
|
def begin_db_transaction #:nodoc:
|
|
catch_schema_changes { @connection.transaction }
|
|
end
|
|
|
|
def commit_db_transaction #:nodoc:
|
|
catch_schema_changes { @connection.commit }
|
|
end
|
|
|
|
def rollback_db_transaction #:nodoc:
|
|
catch_schema_changes { @connection.rollback }
|
|
end
|
|
|
|
|
|
# SELECT ... FOR UPDATE is redundant since the table is locked.
|
|
def add_lock!(sql, options) #:nodoc:
|
|
sql
|
|
end
|
|
|
|
|
|
# SCHEMA STATEMENTS ========================================
|
|
|
|
def tables(name = nil) #:nodoc:
|
|
execute("SELECT name FROM sqlite_master WHERE type = 'table'", name).map do |row|
|
|
row[0]
|
|
end
|
|
end
|
|
|
|
def columns(table_name, name = nil) #:nodoc:
|
|
table_structure(table_name).map do |field|
|
|
SQLiteColumn.new(field['name'], field['dflt_value'], field['type'], field['notnull'] == "0")
|
|
end
|
|
end
|
|
|
|
def indexes(table_name, name = nil) #:nodoc:
|
|
execute("PRAGMA index_list(#{table_name})", name).map do |row|
|
|
index = IndexDefinition.new(table_name, row['name'])
|
|
index.unique = row['unique'] != '0'
|
|
index.columns = execute("PRAGMA index_info('#{index.name}')").map { |col| col['name'] }
|
|
index
|
|
end
|
|
end
|
|
|
|
def primary_key(table_name) #:nodoc:
|
|
column = table_structure(table_name).find {|field| field['pk'].to_i == 1}
|
|
column ? column['name'] : nil
|
|
end
|
|
|
|
def remove_index(table_name, options={}) #:nodoc:
|
|
execute "DROP INDEX #{quote_column_name(index_name(table_name, options))}"
|
|
end
|
|
|
|
def rename_table(name, new_name)
|
|
execute "ALTER TABLE #{name} RENAME TO #{new_name}"
|
|
end
|
|
|
|
def add_column(table_name, column_name, type, options = {}) #:nodoc:
|
|
super(table_name, column_name, type, options)
|
|
# See last paragraph on http://www.sqlite.org/lang_altertable.html
|
|
execute "VACUUM"
|
|
end
|
|
|
|
def remove_column(table_name, column_name) #:nodoc:
|
|
alter_table(table_name) do |definition|
|
|
definition.columns.delete(definition[column_name])
|
|
end
|
|
end
|
|
|
|
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(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
|
|
end
|
|
end
|
|
end
|
|
|
|
def rename_column(table_name, column_name, new_column_name) #:nodoc:
|
|
alter_table(table_name, :rename => {column_name => new_column_name})
|
|
end
|
|
|
|
|
|
protected
|
|
def table_structure(table_name)
|
|
returning structure = execute("PRAGMA table_info(#{table_name})") do
|
|
raise ActiveRecord::StatementInvalid if structure.empty?
|
|
end
|
|
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:
|
|
create_table(to, options) do |@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,
|
|
:null => column.null)
|
|
end
|
|
@definition.primary_key(primary_key(from))
|
|
yield @definition if block_given?
|
|
end
|
|
|
|
copy_table_indexes(from, to)
|
|
copy_table_contents(from, to,
|
|
@definition.columns.map {|column| column.name},
|
|
options[:rename] || {})
|
|
end
|
|
|
|
def copy_table_indexes(from, to) #: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
|
|
|
|
# index name can't be the same
|
|
opts = { :name => name.gsub(/_(#{from})_/, "_#{to}_") }
|
|
opts[:unique] = true if index.unique
|
|
add_index(to, index.columns, opts)
|
|
end
|
|
end
|
|
|
|
def copy_table_contents(from, to, columns, rename = {}) #:nodoc:
|
|
column_mappings = Hash[*columns.map {|name| [name, name]}.flatten]
|
|
rename.inject(column_mappings) {|map, a| map[a.last] = a.first; map}
|
|
from_columns = columns(from).collect {|col| col.name}
|
|
columns = columns.find_all{|col| from_columns.include?(column_mappings[col])}
|
|
@connection.execute "SELECT * FROM #{from}" do |row|
|
|
sql = "INSERT INTO #{to} ("+columns*','+") VALUES ("
|
|
sql << columns.map {|col| quote row[column_mappings[col]]} * ', '
|
|
sql << ')'
|
|
@connection.execute sql
|
|
end
|
|
end
|
|
|
|
def catch_schema_changes
|
|
return yield
|
|
rescue ActiveRecord::StatementInvalid => exception
|
|
if exception.message =~ /database schema has changed/
|
|
reconnect!
|
|
retry
|
|
else
|
|
raise
|
|
end
|
|
end
|
|
end
|
|
|
|
class SQLite3Adapter < SQLiteAdapter # :nodoc:
|
|
def table_structure(table_name)
|
|
returning structure = @connection.table_info(table_name) do
|
|
raise ActiveRecord::StatementInvalid if structure.empty?
|
|
end
|
|
end
|
|
end
|
|
|
|
class SQLite2Adapter < SQLiteAdapter # :nodoc:
|
|
# SQLite 2 does not support COUNT(DISTINCT) queries:
|
|
#
|
|
# select COUNT(DISTINCT ArtistID) from CDs;
|
|
#
|
|
# In order to get the number of artists we execute the following statement
|
|
#
|
|
# SELECT COUNT(ArtistID) FROM (SELECT DISTINCT ArtistID FROM CDs);
|
|
def execute(sql, name = nil) #:nodoc:
|
|
super(rewrite_count_distinct_queries(sql), name)
|
|
end
|
|
|
|
def rewrite_count_distinct_queries(sql)
|
|
if sql =~ /count\(distinct ([^\)]+)\)( AS \w+)? (.*)/i
|
|
distinct_column = $1
|
|
distinct_query = $3
|
|
column_name = distinct_column.split('.').last
|
|
"SELECT COUNT(#{column_name}) FROM (SELECT DISTINCT #{distinct_column} #{distinct_query})"
|
|
else
|
|
sql
|
|
end
|
|
end
|
|
|
|
def rename_table(name, new_name)
|
|
move_table(name, new_name)
|
|
end
|
|
|
|
def add_column(table_name, column_name, type, options = {}) #:nodoc:
|
|
alter_table(table_name) do |definition|
|
|
definition.column(column_name, type, options)
|
|
end
|
|
end
|
|
|
|
end
|
|
|
|
class DeprecatedSQLiteAdapter < SQLite2Adapter # :nodoc:
|
|
def insert(sql, name = nil, pk = nil, id_value = nil)
|
|
execute(sql, name = nil)
|
|
id_value || @connection.last_insert_rowid
|
|
end
|
|
end
|
|
end
|
|
end
|