1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
|
require 'set'
module ActiveRecord
# :stopdoc:
module ConnectionAdapters
# An abstract definition of a column in a table.
class Column
TRUE_VALUES = [true, 1, '1', 't', 'T', 'true', 'TRUE', 'on', 'ON'].to_set
FALSE_VALUES = [false, 0, '0', 'f', 'F', 'false', 'FALSE', 'off', 'OFF'].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, :coder
alias :encoded? :coder
# 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 used to extract the column's length, if necessary. For example +60+ in
# <tt>company_name varchar(60)</tt>.
# It will be mapped to one of the standard Rails SQL types in the <tt>type</tt> attribute.
# +null+ determines if this column allows +NULL+ values.
def initialize(name, default, sql_type = nil, null = true)
@name = name
@sql_type = sql_type
@null = null
@limit = extract_limit(sql_type)
@precision = extract_precision(sql_type)
@scale = extract_scale(sql_type)
@type = simplified_type(sql_type)
@default = extract_default(default)
@primary = nil
@coder = 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, :timestamp, :time then Time
when :date then Date
when :text, :string, :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?
return coder.load(value) if encoded?
klass = self.class
case type
when :string, :text then value
when :integer then value.to_i rescue value ? 1 : 0
when :float then value.to_f
when :decimal then klass.value_to_decimal(value)
when :datetime, :timestamp then klass.string_to_time(value)
when :time then klass.string_to_dummy_time(value)
when :date then klass.string_to_date(value)
when :binary then klass.binary_to_string(value)
when :boolean then klass.value_to_boolean(value)
else value
end
end
def type_cast_code(var_name)
klass = self.class.name
case type
when :string, :text then var_name
when :integer then "(#{var_name}.to_i rescue #{var_name} ? 1 : 0)"
when :float then "#{var_name}.to_f"
when :decimal then "#{klass}.value_to_decimal(#{var_name})"
when :datetime, :timestamp then "#{klass}.string_to_time(#{var_name})"
when :time then "#{klass}.string_to_dummy_time(#{var_name})"
when :date then "#{klass}.string_to_date(#{var_name})"
when :binary then "#{klass}.binary_to_string(#{var_name})"
when :boolean then "#{klass}.value_to_boolean(#{var_name})"
else var_name
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
# Used to convert from Strings to BLOBs
def string_to_binary(value)
self.class.string_to_binary(value)
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] ? (time[:sec_fraction] * 1_000_000).to_i : 0
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 && mon == 0 && mday == 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_r * 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
end
# :startdoc:
end
|