require 'active_support/core_ext/object/blank'
require 'date'
require 'set'
require 'bigdecimal'
require 'bigdecimal/util'
module ActiveRecord
module ConnectionAdapters #:nodoc:
# An abstract definition of a column in a table.
class Column
TRUE_VALUES = [true, 1, '1', 't', 'T', 'true', 'TRUE'].to_set
FALSE_VALUES = [false, 0, '0', 'f', 'F', 'false', 'FALSE'].to_set
module Format
ISO_DATE = /\A(\d{4})-(\d\d)-(\d\d)\z/
ISO_DATETIME = /\A(\d{4})-(\d\d)-(\d\d) (\d\d):(\d\d):(\d\d)(\.\d+)?\z/
end
attr_reader :name, :default, :type, :limit, :null, :sql_type, :precision, :scale
attr_accessor :primary
# Instantiates a new column in the table.
#
# +name+ is the column's name, such as <tt>supplier_id</tt> in <tt>supplier_id int(11)</tt>.
# +default+ is the type-casted default value, such as +new+ in <tt>sales_stage varchar(20) default 'new'</tt>.
# +sql_type+ is only used to extract the column's length, if necessary. For example +60+ in <tt>company_name varchar(60)</tt>.
# +null+ determines if this column allows +NULL+ values.
def initialize(name, default, sql_type = nil, null = true)
@name, @sql_type, @null = name, sql_type, null
@limit, @precision, @scale = extract_limit(sql_type), extract_precision(sql_type), extract_scale(sql_type)
@type = simplified_type(sql_type)
@default = extract_default(default)
@primary = nil
end
# Returns +true+ if the column is either of type string or text.
def text?
type == :string || type == :text
end
# Returns +true+ if the column is either of type integer, float or decimal.
def number?
type == :integer || type == :float || type == :decimal
end
def has_default?
!default.nil?
end
# Returns the Ruby class that corresponds to the abstract data type.
def klass
case type
when :integer then Fixnum
when :float then Float
when :decimal then BigDecimal
when :datetime then Time
when :date then Date
when :timestamp then Time
when :time then Time
when :text, :string then String
when :binary then String
when :boolean then Object
end
end
# Casts value (which is a String) to an appropriate instance.
def type_cast(value)
return nil if value.nil?
case type
when :string then value
when :text then value
when :integer then value.to_i rescue value ? 1 : 0
when :float then value.to_f
when :decimal then self.class.value_to_decimal(value)
when :datetime then self.class.string_to_time(value)
when :timestamp then self.class.string_to_time(value)
when :time then self.class.string_to_dummy_time(value)
when :date then self.class.string_to_date(value)
when :binary then self.class.binary_to_string(value)
when :boolean then self.class.value_to_boolean(value)
else value
end
end
def type_cast_code(var_name)
case type
when :string then nil
when :text then nil
when :integer then "(#{var_name}.to_i rescue #{var_name} ? 1 : 0)"
when :float then "#{var_name}.to_f"
when :decimal then "#{self.class.name}.value_to_decimal(#{var_name})"
when :datetime then "#{self.class.name}.string_to_time(#{var_name})"
when :timestamp then "#{self.class.name}.string_to_time(#{var_name})"
when :time then "#{self.class.name}.string_to_dummy_time(#{var_name})"
when :date then "#{self.class.name}.string_to_date(#{var_name})"
when :binary then "#{self.class.name}.binary_to_string(#{var_name})"
when :boolean then "#{self.class.name}.value_to_boolean(#{var_name})"
else nil
end
end
# Returns the human name of the column name.
#
# ===== Examples
# Column.new('sales_stage', ...).human_name # => 'Sales stage'
def human_name
Base.human_attribute_name(@name)
end
def extract_default(default)
type_cast(default)
end
class << self
# Used to convert from Strings to BLOBs
def string_to_binary(value)
value
end
# Used to convert from BLOBs to Strings
def binary_to_string(value)
value
end
def string_to_date(string)
return string unless string.is_a?(String)
return nil if string.empty?
fast_string_to_date(string) || fallback_string_to_date(string)
end
def string_to_time(string)
return string unless string.is_a?(String)
return nil if string.empty?
fast_string_to_time(string) || fallback_string_to_time(string)
end
def string_to_dummy_time(string)
return string unless string.is_a?(String)
return nil if string.empty?
string_to_time "2000-01-01 #{string}"
end
# convert something to a boolean
def value_to_boolean(value)
if value.is_a?(String) && value.blank?
nil
else
TRUE_VALUES.include?(value)
end
end
# convert something to a BigDecimal
def value_to_decimal(value)
# Using .class is faster than .is_a? and
# subclasses of BigDecimal will be handled
# in the else clause
if value.class == BigDecimal
value
elsif value.respond_to?(:to_d)
value.to_d
else
value.to_s.to_d
end
end
protected
# '0.123456' -> 123456
# '1.123456' -> 123456
def microseconds(time)
((time[:sec_fraction].to_f % 1) * 1_000_000).to_i
end
def new_date(year, mon, mday)
if year && year != 0
Date.new(year, mon, mday) rescue nil
end
end
def new_time(year, mon, mday, hour, min, sec, microsec)
# Treat 0000-00-00 00:00:00 as nil.
return nil if year.nil? || year == 0
Time.time_with_datetime_fallback(Base.default_timezone, year, mon, mday, hour, min, sec, microsec) rescue nil
end
def fast_string_to_date(string)
if string =~ Format::ISO_DATE
new_date $1.to_i, $2.to_i, $3.to_i
end
end
# Doesn't handle time zones.
def fast_string_to_time(string)
if string =~ Format::ISO_DATETIME
microsec = ($7.to_f * 1_000_000).to_i
new_time $1.to_i, $2.to_i, $3.to_i, $4.to_i, $5.to_i, $6.to_i, microsec
end
end
def fallback_string_to_date(string)
new_date(*::Date._parse(string, false).values_at(:year, :mon, :mday))
end
def fallback_string_to_time(string)
time_hash = Date._parse(string)
time_hash[:sec_fraction] = microseconds(time_hash)
new_time(*time_hash.values_at(:year, :mon, :mday, :hour, :min, :sec, :sec_fraction))
end
end
private
def extract_limit(sql_type)
$1.to_i if sql_type =~ /\((.*)\)/
end
def extract_precision(sql_type)
$2.to_i if sql_type =~ /^(numeric|decimal|number)\((\d+)(,\d+)?\)/i
end
def extract_scale(sql_type)
case sql_type
when /^(numeric|decimal|number)\((\d+)\)/i then 0
when /^(numeric|decimal|number)\((\d+)(,(\d+))\)/i then $4.to_i
end
end
def simplified_type(field_type)
case field_type
when /int/i
:integer
when /float|double/i
:float
when /decimal|numeric|number/i
extract_scale(field_type) == 0 ? :integer : :decimal
when /datetime/i
:datetime
when /timestamp/i
:timestamp
when /time/i
:time
when /date/i
:date
when /clob/i, /text/i
:text
when /blob/i, /binary/i
:binary
when /char/i, /string/i
:string
when /boolean/i
:boolean
end
end
end
class IndexDefinition < Struct.new(:table, :name, :unique, :columns) #:nodoc:
end
# Abstract representation of a column definition. Instances of this type
# are typically created by methods in TableDefinition, and added to the
# +columns+ attribute of said TableDefinition object, in order to be used
# for generating a number of table creation or table changing SQL statements.
class ColumnDefinition < Struct.new(:base, :name, :type, :limit, :precision, :scale, :default, :null) #:nodoc:
def sql_type
base.type_to_sql(type.to_sym, limit, precision, scale) rescue type
end
def to_sql
column_sql = "#{base.quote_column_name(name)} #{sql_type}"
column_options = {}
column_options[:null] = null unless null.nil?
column_options[:default] = default unless default.nil?
add_column_options!(column_sql, column_options) unless type.to_sym == :primary_key
column_sql
end
private
def add_column_options!(sql, options)
base.add_column_options!(sql, options.merge(:column => self))
end
end
# Represents the schema of an SQL table in an abstract way. This class
# provides methods for manipulating the schema representation.
#
# Inside migration files, the +t+ object in +create_table+ and
# +change_table+ is actually of this type:
#
# class SomeMigration < ActiveRecord::Migration
# def self.up
# create_table :foo do |t|
# puts t.class # => "ActiveRecord::ConnectionAdapters::TableDefinition"
# end
# end
#
# def self.down
# ...
# end
# end
#
# The table definitions
# The Columns are stored as a ColumnDefinition in the +columns+ attribute.
class TableDefinition
# An array of ColumnDefinition objects, representing the column changes
# that have been defined.
attr_accessor :columns
def initialize(base)
@columns = []
@base = base
end
#Handles non supported datatypes - e.g. XML
def method_missing(symbol, *args)
if symbol.to_s == 'xml'
xml_column_fallback(args)
else
super
end
end
def xml_column_fallback(*args)
case @base.adapter_name.downcase
when 'sqlite', 'mysql'
options = args.extract_options!
column(args[0], :text, options)
end
end
# Appends a primary key definition to the table definition.
# Can be called multiple times, but this is probably not a good idea.
def primary_key(name)
column(name, :primary_key)
end
# Returns a ColumnDefinition for the column with name +name+.
def [](name)
@columns.find {|column| column.name.to_s == name.to_s}
end
# Instantiates a new column for the table.
# The +type+ parameter is normally one of the migrations native types,
# which is one of the following:
# <tt>:primary_key</tt>, <tt>:string</tt>, <tt>:text</tt>,
# <tt>:integer</tt>, <tt>:float</tt>, <tt>:decimal</tt>,
# <tt>:datetime</tt>, <tt>:timestamp</tt>, <tt>:time</tt>,
# <tt>:date</tt>, <tt>:binary</tt>, <tt>:boolean</tt>.
#
# You may use a type not in this list as long as it is supported by your
# database (for example, "polygon" in MySQL), but this will not be database
# agnostic and should usually be avoided.
#
# Available options are (none of these exists by default):
# * <tt>:limit</tt> -
# Requests a maximum column length. This is number of characters for <tt>:string</tt> and <tt>:text</tt> columns and number of bytes for :binary and :integer columns.
# * <tt>:default</tt> -
# The column's default value. Use nil for NULL.
# * <tt>:null</tt> -
# Allows or disallows +NULL+ values in the column. This option could
# have been named <tt>:null_allowed</tt>.
# * <tt>:precision</tt> -
# Specifies the precision for a <tt>:decimal</tt> column.
# * <tt>:scale</tt> -
# Specifies the scale for a <tt>:decimal</tt> column.
#
# For clarity's sake: the precision is the number of significant digits,
# while the scale is the number of digits that can be stored following
# the decimal point. For example, the number 123.45 has a precision of 5
# and a scale of 2. A decimal with a precision of 5 and a scale of 2 can
# range from -999.99 to 999.99.
#
# Please be aware of different RDBMS implementations behavior with
# <tt>:decimal</tt> columns:
# * The SQL standard says the default scale should be 0, <tt>:scale</tt> <=
# <tt>:precision</tt>, and makes no comments about the requirements of
# <tt>:precision</tt>.
# * MySQL: <tt>:precision</tt> [1..63], <tt>:scale</tt> [0..30].
# Default is (10,0).
# * PostgreSQL: <tt>:precision</tt> [1..infinity],
# <tt>:scale</tt> [0..infinity]. No default.
# * SQLite2: Any <tt>:precision</tt> and <tt>:scale</tt> may be used.
# Internal storage as strings. No default.
# * SQLite3: No restrictions on <tt>:precision</tt> and <tt>:scale</tt>,
# but the maximum supported <tt>:precision</tt> is 16. No default.
# * Oracle: <tt>:precision</tt> [1..38], <tt>:scale</tt> [-84..127].
# Default is (38,0).
# * DB2: <tt>:precision</tt> [1..63], <tt>:scale</tt> [0..62].
# Default unknown.
# * Firebird: <tt>:precision</tt> [1..18], <tt>:scale</tt> [0..18].
# Default (9,0). Internal types NUMERIC and DECIMAL have different
# storage rules, decimal being better.
# * FrontBase?: <tt>:precision</tt> [1..38], <tt>:scale</tt> [0..38].
# Default (38,0). WARNING Max <tt>:precision</tt>/<tt>:scale</tt> for
# NUMERIC is 19, and DECIMAL is 38.
# * SqlServer?: <tt>:precision</tt> [1..38], <tt>:scale</tt> [0..38].
# Default (38,0).
# * Sybase: <tt>:precision</tt> [1..38], <tt>:scale</tt> [0..38].
# Default (38,0).
# * OpenBase?: Documentation unclear. Claims storage in <tt>double</tt>.
#
# This method returns <tt>self</tt>.
#
# == Examples
# # Assuming td is an instance of TableDefinition
# td.column(:granted, :boolean)
# # granted BOOLEAN
#
# td.column(:picture, :binary, :limit => 2.megabytes)
# # => picture BLOB(2097152)
#
# td.column(:sales_stage, :string, :limit => 20, :default => 'new', :null => false)
# # => sales_stage VARCHAR(20) DEFAULT 'new' NOT NULL
#
# td.column(:bill_gates_money, :decimal, :precision => 15, :scale => 2)
# # => bill_gates_money DECIMAL(15,2)
#
# td.column(:sensor_reading, :decimal, :precision => 30, :scale => 20)
# # => sensor_reading DECIMAL(30,20)
#
# # While <tt>:scale</tt> defaults to zero on most databases, it
# # probably wouldn't hurt to include it.
# td.column(:huge_integer, :decimal, :precision => 30)
# # => huge_integer DECIMAL(30)
#
# # Defines a column with a database-specific type.
# td.column(:foo, 'polygon')
# # => foo polygon
#
# == Short-hand examples
#
# Instead of calling +column+ directly, you can also work with the short-hand definitions for the default types.
# They use the type as the method name instead of as a parameter and allow for multiple columns to be defined
# in a single statement.
#
# What can be written like this with the regular calls to column:
#
# create_table "products", :force => true do |t|
# t.column "shop_id", :integer
# t.column "creator_id", :integer
# t.column "name", :string, :default => "Untitled"
# t.column "value", :string, :default => "Untitled"
# t.column "created_at", :datetime
# t.column "updated_at", :datetime
# end
#
# Can also be written as follows using the short-hand:
#
# create_table :products do |t|
# t.integer :shop_id, :creator_id
# t.string :name, :value, :default => "Untitled"
# t.timestamps
# end
#
# There's a short-hand method for each of the type values declared at the top. And then there's
# TableDefinition#timestamps that'll add created_at and +updated_at+ as datetimes.
#
# TableDefinition#references will add an appropriately-named _id column, plus a corresponding _type
# column if the <tt>:polymorphic</tt> option is supplied. If <tt>:polymorphic</tt> is a hash of options, these will be
# used when creating the <tt>_type</tt> column. So what can be written like this:
#
# create_table :taggings do |t|
# t.integer :tag_id, :tagger_id, :taggable_id
# t.string :tagger_type
# t.string :taggable_type, :default => 'Photo'
# end
#
# Can also be written as follows using references:
#
# create_table :taggings do |t|
# t.references :tag
# t.references :tagger, :polymorphic => true
# t.references :taggable, :polymorphic => { :default => 'Photo' }
# end
def column(name, type, options = {})
column = self[name] || ColumnDefinition.new(@base, name, type)
if options[:limit]
column.limit = options[:limit]
elsif native[type.to_sym].is_a?(Hash)
column.limit = native[type.to_sym][:limit]
end
column.precision = options[:precision]
column.scale = options[:scale]
column.default = options[:default]
column.null = options[:null]
@columns << column unless @columns.include? column
self
end
%w( string text integer float decimal datetime timestamp time date binary boolean ).each do |column_type|
class_eval <<-EOV
def #{column_type}(*args) # def string(*args)
options = args.extract_options! # options = args.extract_options!
column_names = args # column_names = args
#
column_names.each { |name| column(name, '#{column_type}', options) } # column_names.each { |name| column(name, 'string', options) }
end # end
EOV
end
# Appends <tt>:datetime</tt> columns <tt>:created_at</tt> and
# <tt>:updated_at</tt> to the table.
def timestamps(*args)
options = args.extract_options!
column(:created_at, :datetime, options)
column(:updated_at, :datetime, options)
end
def references(*args)
options = args.extract_options!
polymorphic = options.delete(:polymorphic)
args.each do |col|
column("#{col}_id", :integer, options)
column("#{col}_type", :string, polymorphic.is_a?(Hash) ? polymorphic : options) unless polymorphic.nil?
end
end
alias :belongs_to :references
# Returns a String whose contents are the column definitions
# concatenated together. This string can then be prepended and appended to
# to generate the final SQL to create the table.
def to_sql
@columns.map(&:to_sql) * ', '
end
private
def native
@base.native_database_types
end
end
# Represents a SQL table in an abstract way for updating a table.
# Also see TableDefinition and SchemaStatements#create_table
#
# Available transformations are:
#
# change_table :table do |t|
# t.column
# t.index
# t.timestamps
# t.change
# t.change_default
# t.rename
# t.references
# t.belongs_to
# t.string
# t.text
# t.integer
# t.float
# t.decimal
# t.datetime
# t.timestamp
# t.time
# t.date
# t.binary
# t.boolean
# t.remove
# t.remove_references
# t.remove_belongs_to
# t.remove_index
# t.remove_timestamps
# end
#
class Table
def initialize(table_name, base)
@table_name = table_name
@base = base
end
# Adds a new column to the named table.
# See TableDefinition#column for details of the options you can use.
# ===== Example
# ====== Creating a simple column
# t.column(:name, :string)
def column(column_name, type, options = {})
@base.add_column(@table_name, column_name, type, options)
end
# Adds a new index to the table. +column_name+ can be a single Symbol, or
# an Array of Symbols. See SchemaStatements#add_index
#
# ===== Examples
# ====== Creating a simple index
# t.index(:name)
# ====== Creating a unique index
# t.index([:branch_id, :party_id], :unique => true)
# ====== Creating a named index
# t.index([:branch_id, :party_id], :unique => true, :name => 'by_branch_party')
def index(column_name, options = {})
@base.add_index(@table_name, column_name, options)
end
# Adds timestamps (created_at and updated_at) columns to the table. See SchemaStatements#add_timestamps
# ===== Example
# t.timestamps
def timestamps
@base.add_timestamps(@table_name)
end
# Changes the column's definition according to the new options.
# See TableDefinition#column for details of the options you can use.
# ===== Examples
# t.change(:name, :string, :limit => 80)
# t.change(:description, :text)
def change(column_name, type, options = {})
@base.change_column(@table_name, column_name, type, options)
end
# Sets a new default value for a column. See SchemaStatements#change_column_default
# ===== Examples
# t.change_default(:qualification, 'new')
# t.change_default(:authorized, 1)
def change_default(column_name, default)
@base.change_column_default(@table_name, column_name, default)
end
# Removes the column(s) from the table definition.
# ===== Examples
# t.remove(:qualification)
# t.remove(:qualification, :experience)
def remove(*column_names)
@base.remove_column(@table_name, column_names)
end
# Removes the given index from the table.
#
# ===== Examples
# ====== Remove the suppliers_name_index in the suppliers table
# t.remove_index :name
# ====== Remove the index named accounts_branch_id_index in the accounts table
# t.remove_index :column => :branch_id
# ====== Remove the index named accounts_branch_id_party_id_index in the accounts table
# t.remove_index :column => [:branch_id, :party_id]
# ====== Remove the index named by_branch_party in the accounts table
# t.remove_index :name => :by_branch_party
def remove_index(options = {})
@base.remove_index(@table_name, options)
end
# Removes the timestamp columns (created_at and updated_at) from the table.
# ===== Example
# t.remove_timestamps
def remove_timestamps
@base.remove_timestamps(@table_name)
end
# Renames a column.
# ===== Example
# t.rename(:description, :name)
def rename(column_name, new_column_name)
@base.rename_column(@table_name, column_name, new_column_name)
end
# Adds a reference. Optionally adds a +type+ column.
# <tt>references</tt> and <tt>belongs_to</tt> are acceptable.
# ===== Examples
# t.references(:goat)
# t.references(:goat, :polymorphic => true)
# t.belongs_to(:goat)
def references(*args)
options = args.extract_options!
polymorphic = options.delete(:polymorphic)
args.each do |col|
@base.add_column(@table_name, "#{col}_id", :integer, options)
@base.add_column(@table_name, "#{col}_type", :string, polymorphic.is_a?(Hash) ? polymorphic : options) unless polymorphic.nil?
end
end
alias :belongs_to :references
# Removes a reference. Optionally removes a +type+ column.
# <tt>remove_references</tt> and <tt>remove_belongs_to</tt> are acceptable.
# ===== Examples
# t.remove_references(:goat)
# t.remove_references(:goat, :polymorphic => true)
# t.remove_belongs_to(:goat)
def remove_references(*args)
options = args.extract_options!
polymorphic = options.delete(:polymorphic)
args.each do |col|
@base.remove_column(@table_name, "#{col}_id")
@base.remove_column(@table_name, "#{col}_type") unless polymorphic.nil?
end
end
alias :remove_belongs_to :remove_references
# Adds a column or columns of a specified type
# ===== Examples
# t.string(:goat)
# t.string(:goat, :sheep)
%w( string text integer float decimal datetime timestamp time date binary boolean ).each do |column_type|
class_eval <<-EOV
def #{column_type}(*args) # def string(*args)
options = args.extract_options! # options = args.extract_options!
column_names = args # column_names = args
#
column_names.each do |name| # column_names.each do |name|
column = ColumnDefinition.new(@base, name, '#{column_type}') # column = ColumnDefinition.new(@base, name, 'string')
if options[:limit] # if options[:limit]
column.limit = options[:limit] # column.limit = options[:limit]
elsif native['#{column_type}'.to_sym].is_a?(Hash) # elsif native['string'.to_sym].is_a?(Hash)
column.limit = native['#{column_type}'.to_sym][:limit] # column.limit = native['string'.to_sym][:limit]
end # end
column.precision = options[:precision] # column.precision = options[:precision]
column.scale = options[:scale] # column.scale = options[:scale]
column.default = options[:default] # column.default = options[:default]
column.null = options[:null] # column.null = options[:null]
@base.add_column(@table_name, name, column.sql_type, options) # @base.add_column(@table_name, name, column.sql_type, options)
end # end
end # end
EOV
end
private
def native
@base.native_database_types
end
end
end
end
