Class: Chicago::Database::ConcreteSchemaStrategy Private

Inherits:
Object
  • Object
show all
Defined in:
lib/chicago/database/concrete_schema_strategies.rb

Overview

This class is part of a private API. You should avoid using this class if possible, as it may be removed or be changed in the future.

Generic database strategy.

This supplements Sequel’s type conversion strategy rather than replaces it, so :boolean will still return :boolean rather than tinyint(1) in the case of mysql.

Direct Known Subclasses

MysqlStrategy, RedshiftStrategy

Class Method Summary collapse

Instance Method Summary collapse

Class Method Details

.for_db(db) ⇒ ConcreteSchemaStrategy

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future.

Factory method that returns an appropriate type conversion stratgey for the given database.

If a database-specific strategy cannot be found, returns a generic strategy.

Returns:



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# File 'lib/chicago/database/concrete_schema_strategies.rb', line 16

def self.for_db(db)
  if db.database_type == :mysql
    MysqlStrategy.new
  elsif db.database_type == :postgres && 
      db.opts[:adapter] == "redshift"
    RedshiftStrategy.new
  else
    self.new
  end
end

Instance Method Details

#column_hash(column) ⇒ Object

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future.

Returns the hash of the column.



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# File 'lib/chicago/database/concrete_schema_strategies.rb', line 46

def column_hash(column)
  hsh = column.to_hash.merge(:column_type => db_type(column))
  hsh.delete(:elements) if hsh.has_key?(:elements)
  hsh
end

#db_type(column) ⇒ Symbol

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future.

Returns a db type given a column definition

Returns:

  • (Symbol) 


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# File 'lib/chicago/database/concrete_schema_strategies.rb', line 60

def db_type(column)
  case column.column_type
  when :integer then integer_type(column.min, column.max)
  when :string  then string_type(column.min, column.max)
  when :money   then :decimal
  when :percent then :decimal
  else
    column.column_type
  end
end

#id_column ⇒ Object

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future.

Returns the definition of the column which should be used as the primary id column.



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# File 'lib/chicago/database/concrete_schema_strategies.rb', line 29

def id_column
  {
    :name => :id,
    :column_type => :integer,
    :unsigned => true
  }
end

#indexes(table) ⇒ Object

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future.

Returns the indexes for the given table.



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# File 'lib/chicago/database/concrete_schema_strategies.rb', line 53

def indexes(table)
  IndexGenerator.new(table).indexes
end

#integer_type(min, max) ⇒ Symbol

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future.

Returns a database integer column type, big enough to fit values between min and max, or integer if a specific type cannot be found.

Returns:

  • (Symbol)

Raises:

  • an ArgumentError if min or max is too large for a single database column.



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# File 'lib/chicago/database/concrete_schema_strategies.rb', line 95

def integer_type(min, max)
  if min && max && in_numeric_range?(min, max, SMALL_INT_MAX)
    :smallint
  else
    :integer
  end
end

#migration_options ⇒ Object

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future.

Returns options to be passed to the Migration Builder.

Empty by default, may be overridden by subclasses for specific databases.



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# File 'lib/chicago/database/concrete_schema_strategies.rb', line 41

def migration_options
  {}
end

#string_type(min, max) ⇒ Symbol

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future.

Returns a database type for a string column.

Returns:

  • (Symbol) 


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# File 'lib/chicago/database/concrete_schema_strategies.rb', line 84

def string_type(min, max)
  min && max && min == max ? :char : :varchar 
end

#table_options ⇒ Hash

This method is part of a private API. You should avoid using this method if possible, as it may be removed or be changed in the future.

Returns sequel table options for a dimension or fact table.

None by default, but database-specific subclasses may override this.

Returns:



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# File 'lib/chicago/database/concrete_schema_strategies.rb', line 77

def table_options
  {}
end