Class: SQLConstructor::BasicJoin_mysql

Inherits:

BasicJoin

• Object
• SQLObject
• GenericQuery
• BasicJoin
• SQLConstructor::BasicJoin_mysql

Defined in:

lib/dialects/mysql-constructor.rb

Overview

MySQL dialect descendant of BasicJoin class

Constant Summary

VALID_JOINS =

[ "join", "inner_join", "cross_join", "left_join", "right_join", 
"left_outer_join", "right_outer_join",
"natural_join", "natural_left_join", "natural_right_join", 
"natural_left_outer_join", "natural_right_outer_join" ]

Constants inherited from BasicJoin

SQLConstructor::BasicJoin::METHODS

Instance Attribute Summary

Attributes inherited from BasicJoin

#join_on, #join_sources, #join_using

Attributes inherited from GenericQuery

#attr_index_hints, #caller, #child_caller, #dialect, #exporter, #string, #tidy, #type

Attributes inherited from SQLObject

#alias, #inline, #name, #separator

Instance Method Summary

• #_addIndexes(type, *list) ⇒ Object

  Adds a USE/FORCE/IGNORE INDEX clause for the last objects in for_vals argument.

• #initialize(_caller, type, *sources) ⇒ BasicJoin_mysql constructor

  Class contructor.

• #method_missing(method, *args) ⇒ Object

  Handles INDEX hints or sends the call to the parent.

• #to_s ⇒ Object

  Export to string with index hints included.

Methods inherited from BasicJoin

#join_more

Methods inherited from GenericQuery

#_get, #_remove, #to_str

Methods inherited from SQLObject

#_name, #_string, #_string=, get

Constructor Details

#initialize(_caller, type, *sources) ⇒ BasicJoin_mysql

Class contructor. Takes a caller object as the first argument, JOIN

type as the second argument, and a list of sources for the JOIN clause

# File 'lib/dialects/mysql-constructor.rb', line 181

def initialize ( _caller, type, *sources )
    type = type.to_s
    if ! VALID_JOINS.include? type
        raise NoMethodError, ERR_UNKNOWN_METHOD + ": " + type
    end
    super
end

Dynamic Method Handling

This class handles dynamic methods through the method_missing method

#method_missing(method, *args) ⇒ Object

Handles INDEX hints or sends the call to the parent

# File 'lib/dialects/mysql-constructor.rb', line 218

def method_missing ( method, *args )
     # Handle all valid *_index/*_key calls:
    return _addIndexes( method, *args )  if VALID_INDEX_HINTS.include? method 
    super
end

Instance Method Details

#_addIndexes(type, *list) ⇒ Object

Adds a USE/FORCE/IGNORE INDEX clause for the last objects in for_vals

argument.

# File 'lib/dialects/mysql-constructor.rb', line 193

def _addIndexes ( type, *list )
    type = type.to_s
    type.upcase!.gsub! /_/, ' '
    @attr_index_hints ||= [ ]
     # set the attr_index_hints for the last object in for_vals
    last_ind = @join_sources.length - 1
    @attr_index_hints[last_ind] = { :type => type, :list => SQLObject.get( list ) }
    @string = nil
    return self
end

#to_s ⇒ Object

Export to string with index hints included

# File 'lib/dialects/mysql-constructor.rb', line 207

def to_s
    return @string  if @string
    result  = @type + " " + to_sWithAliasesIndexes( @join_sources )
    result += @exporter.separator
    result += "ON " + @join_on.val.to_s  if @join_on
    @string = result
end