Class ActiveRecord::ConnectionAdapters::TableDefinition
In: vendor/rails/activerecord/lib/active_record/connection_adapters/abstract/schema_definitions.rb
Parent: Object

Represents a SQL table in an abstract way. Columns are stored as ColumnDefinition in the columns attribute.

Methods

[]   column   new   primary_key   to_sql  

Attributes

columns  [RW] 

Public Class methods

new(base)

[Source]

     # File vendor/rails/activerecord/lib/active_record/connection_adapters/abstract/schema_definitions.rb, line 190
190:       def initialize(base)
191:         @columns = []
192:         @base = base
193:       end

Public Instance methods

[](name)

Returns a ColumnDefinition for the column with name name.

[Source]

     # File vendor/rails/activerecord/lib/active_record/connection_adapters/abstract/schema_definitions.rb, line 202
202:       def [](name)
203:         @columns.find {|column| column.name.to_s == name.to_s}
204:       end
column(name, type, options = {})

Instantiates a new column for the table. The type parameter must be one of the following values: :primary_key, :string, :text, :integer, :float, :datetime, :timestamp, :time, :date, :binary, :boolean.

Available options are (none of these exists by default):

  • :limit: Requests a maximum column length (:string, :text, :binary or :integer columns only)
  • :default: The column’s default value. You cannot explicitely set the default value to NULL. Simply leave off this option if you want a NULL default value.
  • :null: Allows or disallows NULL values in the column. This option could have been named :null_allowed.

This method returns self.

Examples
 # Assuming def is an instance of TableDefinition
 def.column(:granted, :boolean)
   #=> granted BOOLEAN

 def.column(:picture, :binary, :limit => 2.megabytes)
   #=> picture BLOB(2097152)

 def.column(:sales_stage, :string, :limit => 20, :default => 'new', :null => false)
   #=> sales_stage VARCHAR(20) DEFAULT 'new' NOT NULL

[Source]

     # File vendor/rails/activerecord/lib/active_record/connection_adapters/abstract/schema_definitions.rb, line 237
237:       def column(name, type, options = {})
238:         column = self[name] || ColumnDefinition.new(@base, name, type)
239:         column.limit = options[:limit] || native[type.to_sym][:limit] if options[:limit] or native[type.to_sym]
240:         column.default = options[:default]
241:         column.null = options[:null]
242:         @columns << column unless @columns.include? column
243:         self
244:       end
primary_key(name)

Appends a primary key definition to the table definition. Can be called multiple times, but this is probably not a good idea.

[Source]

     # File vendor/rails/activerecord/lib/active_record/connection_adapters/abstract/schema_definitions.rb, line 197
197:       def primary_key(name)
198:         column(name, native[:primary_key])
199:       end
to_sql()

Returns a String whose contents are the column definitions concatenated together. This string can then be pre and appended to to generate the final SQL to create the table.

[Source]

     # File vendor/rails/activerecord/lib/active_record/connection_adapters/abstract/schema_definitions.rb, line 249
249:       def to_sql
250:         @columns * ', '
251:       end

[Validate]