Module: SchemaPlus::ActiveRecord::ConnectionAdapters::AbstractAdapter

Defined in:
lib/schema_plus/active_record/connection_adapters/abstract_adapter.rb

Overview

SchemaPlus adds several methods to ActiveRecord::ConnectionAdapters::AbstractAdapter. In most cases you don’t call these directly, but rather the methods that define things are called by schema statements, and methods that query things are called by ActiveRecord::Base.

Defined Under Namespace

Modules: SchemaCreation

Class Method Summary collapse

Instance Method Summary collapse

Class Method Details

.included(base) ⇒ Object

:nodoc:



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# File 'lib/schema_plus/active_record/connection_adapters/abstract_adapter.rb', line 14

def self.included(base) #:nodoc:
  base.alias_method_chain :initialize, :schema_plus
end

Instance Method Details

#add_column_options!(sql, options) ⇒ Object 



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# File 'lib/schema_plus/active_record/connection_adapters/abstract_adapter.rb', line 116

def add_column_options!(sql, options)
  if options_include_default?(options)
    default = options[:default]
    if default.is_a? Hash
      value = default[:value]
      expr = sql_for_function(default[:expr]) || default[:expr] if default[:expr]
    else
      value = default
      expr = sql_for_function(default)
    end
    if expr
      raise ArgumentError, "Invalid default expression" unless default_expr_valid?(expr)
      sql << " DEFAULT #{expr}"
    else
      sql << " DEFAULT #{quote(value, options[:column])}" unless value.nil?
    end
  end
  # must explicitly check for :null to allow change_column to work on migrations
  if options[:null] == false
    sql << " NOT NULL"
  end
end

#add_foreign_key(table_name, column_names, references_table_name, references_column_names, options = {}) ⇒ Object

Define a foreign key constraint. Valid options are :on_update, :on_delete, and :deferrable, with values as described at ConnectionAdapters::ForeignKeyDefinition

(NOTE: Sqlite3 does not support altering a table to add foreign-key constraints; they must be included in the table specification when it’s created. If you’re using Sqlite3, this method will raise an error.)



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# File 'lib/schema_plus/active_record/connection_adapters/abstract_adapter.rb', line 59

def add_foreign_key(table_name, column_names, references_table_name, references_column_names, options = {})
  foreign_key = ForeignKeyDefinition.new(options[:name] || ForeignKeyDefinition.default_name(table_name, column_names), table_name, column_names, ::ActiveRecord::Migrator.proper_table_name(references_table_name), references_column_names, options[:on_update], options[:on_delete], options[:deferrable])
  execute "ALTER TABLE #{quote_table_name(table_name)} ADD #{foreign_key.to_sql}"
end

#create_view(view_name, definition, options = {}) ⇒ Object

Create a view given the SQL definition. Specify :force => true to first drop the view if it already exists.



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# File 'lib/schema_plus/active_record/connection_adapters/abstract_adapter.rb', line 39

def create_view(view_name, definition, options={})
  definition = definition.to_sql if definition.respond_to? :to_sql
  execute "DROP VIEW IF EXISTS #{quote_table_name(view_name)}" if options[:force]
  execute "CREATE VIEW #{quote_table_name(view_name)} AS #{definition}"
end

#default_expr_valid?(expr) ⇒ Boolean

(abstract) Return true if the passed expression can be used as a column default value. (For most databases the specific expression doesn’t matter, and the adapter’s function would return a constant true if default expressions are supported or false if they’re not.)

Returns:

  • (Boolean) 


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# File 'lib/schema_plus/active_record/connection_adapters/abstract_adapter.rb', line 166

def default_expr_valid?(expr) raise "Internal Error: Connection adapter didn't override abstract function"; end

#drop_table(name, options = {}) ⇒ Object

Extends rails’ drop_table to include these options:

:cascade
:if_exists



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# File 'lib/schema_plus/active_record/connection_adapters/abstract_adapter.rb', line 77

def drop_table(name, options = {})
  sql = "DROP TABLE"
  sql += " IF EXISTS" if options[:if_exists]
  sql += " #{quote_table_name(name)}"
  sql += " CASCADE" if options[:cascade]
  execute sql
end

#drop_view(view_name) ⇒ Object

Drop the named view



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# File 'lib/schema_plus/active_record/connection_adapters/abstract_adapter.rb', line 46

def drop_view(view_name)
  execute "DROP VIEW #{quote_table_name(view_name)}"
end

#foreign_keys(table_name, name = nil) ⇒ Object

(abstract) Return the ForeignKeyDefinition objects for foreign key constraints defined on this table



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# File 'lib/schema_plus/active_record/connection_adapters/abstract_adapter.rb', line 155

def foreign_keys(table_name, name = nil) raise "Internal Error: Connection adapter didn't override abstract function"; [] end

#initialize_with_schema_plus(*args) ⇒ Object

:nodoc:



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# File 'lib/schema_plus/active_record/connection_adapters/abstract_adapter.rb', line 18

def initialize_with_schema_plus(*args) #:nodoc:
  initialize_without_schema_plus(*args)
  adapter = case adapter_name
              # name of MySQL adapter depends on mysql gem
              # * with mysql gem adapter is named MySQL
              # * with mysql2 gem adapter is named Mysql2
              # Here we handle this and hopefully futher adapter names
            when /^MySQL/i                 then 'MysqlAdapter'
            when 'PostgreSQL', 'PostGIS'   then 'PostgresqlAdapter'
            when 'SQLite'                  then 'Sqlite3Adapter'
            end or raise "SchemaPlus: Unsupported adapter name #{adapter_name.inspect}"
              # use 'end or raise' instead of 'else raise' to get
              # 100% C0 code coverage despite having no test case
              # for this.
  adapter_module = SchemaPlus::ActiveRecord::ConnectionAdapters.const_get(adapter)
  self.class.send(:include, adapter_module) unless self.class.include?(adapter_module)
  extend(SchemaPlus::ActiveRecord::ForeignKeys)
end

#remove_foreign_key(table_name, foreign_key_name) ⇒ Object

Remove a foreign key constraint

(NOTE: Sqlite3 does not support altering a table to remove foreign-key constraints. If you’re using Sqlite3, this method will raise an error.)



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# File 'lib/schema_plus/active_record/connection_adapters/abstract_adapter.rb', line 69

def remove_foreign_key(table_name, foreign_key_name)
  execute "ALTER TABLE #{quote_table_name(table_name)} DROP CONSTRAINT #{foreign_key_name}"
end

#rename_indexes_and_foreign_keys(oldname, newname) ⇒ Object

called from individual adpaters, after renaming table from old name to



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# File 'lib/schema_plus/active_record/connection_adapters/abstract_adapter.rb', line 87

def rename_indexes_and_foreign_keys(oldname, newname) #:nodoc:
  indexes(newname).select{|index| index.name == index_name(oldname, index.columns)}.each do |index|
    rename_index(newname, index.name, index_name(newname, index.columns))
  end
  foreign_keys(newname).each do |fk|
    index = indexes(newname).find{|index| index.name == ForeignKeyDefinition.auto_index_name(oldname, fk.column_names)}
    begin
      remove_foreign_key(newname, fk.name)
    rescue NotImplementedError
      # sqlite3 can't remove foreign keys, so just skip it
    end
    # rename the index only when the fk constraint doesn't exist.
    # mysql doesn't allow the rename (which is a delete & add)
    # if the index is on a foreign key constraint
    rename_index(newname, index.name, ForeignKeyDefinition.auto_index_name(newname, index.columns)) if index
    begin
      add_foreign_key(newname, fk.column_names, fk.references_table_name, fk.references_column_names, :name => fk.name.sub(/#{oldname}/, newname), :on_update => fk.on_update, :on_delete => fk.on_delete, :deferrable => fk.deferrable)
    rescue NotImplementedError
      # sqlite3 can't add foreign keys, so just skip it
    end
  end
end

#reverse_foreign_keys(table_name, name = nil) ⇒ Object

(abstract) Return the ForeignKeyDefinition objects for foreign key constraints defined on other tables that reference this table



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# File 'lib/schema_plus/active_record/connection_adapters/abstract_adapter.rb', line 159

def reverse_foreign_keys(table_name, name = nil) raise "Internal Error: Connection adapter didn't override abstract function"; [] end

#sql_for_function(function_name) ⇒ Object

(abstract) Return SQL definition for a given canonical function_name symbol. Currently, the only function to support is :now, which should return a DATETIME object for the current time.



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# File 'lib/schema_plus/active_record/connection_adapters/abstract_adapter.rb', line 171

def sql_for_function(function_name) raise "Internal Error: Connection adapter didn't override abstract function"; end

#supports_partial_indexes? ⇒ Boolean

Returns true if the database supports parital indexes (abstract; only Postgresql returns true)

Returns:

  • (Boolean) 


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# File 'lib/schema_plus/active_record/connection_adapters/abstract_adapter.rb', line 112

def supports_partial_indexes?
  false
end

#view_definition(view_name, name = nil) ⇒ Object

(abstract) Returns the SQL definition of a given view. This is the literal SQL would come after ‘CREATVE VIEW viewname AS ’ in the SQL statement to create a view.



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# File 'lib/schema_plus/active_record/connection_adapters/abstract_adapter.rb', line 151

def view_definition(view_name, name = nil) raise "Internal Error: Connection adapter didn't override abstract function"; end

#views(name = nil) ⇒ Object

(abstract) Returns the names of all views, as an array of strings



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# File 'lib/schema_plus/active_record/connection_adapters/abstract_adapter.rb', line 146

def views(name = nil) raise "Internal Error: Connection adapter didn't override abstract function"; [] end