Class: Zdm::Table

Inherits:
Object
  • Object
show all
Defined in:
lib/zdm.rb

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(name) ⇒ Table

Returns a new instance of Table.



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# File 'lib/zdm.rb', line 113

def initialize(name)
  @origin = name
  @copy = "zdm_#{name}"
  @archive = "zdma_#{Time.now.strftime("%Y%m%d_%H%M%S%N")}_#{name}"[0...64]
  @statements = []
end

Instance Attribute Details

#archive ⇒ Object (readonly)

Returns the value of attribute archive.



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# File 'lib/zdm.rb', line 111

def archive
  @archive
end

#copy ⇒ Object (readonly)

Returns the value of attribute copy.



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# File 'lib/zdm.rb', line 111

def copy
  @copy
end

#origin ⇒ Object (readonly)

Returns the value of attribute origin.



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# File 'lib/zdm.rb', line 111

def origin
  @origin
end

#statements ⇒ Object (readonly)

Returns the value of attribute statements.



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# File 'lib/zdm.rb', line 111

def statements
  @statements
end

Instance Method Details

#add_column(name, definition) ⇒ Object 



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# File 'lib/zdm.rb', line 128

def add_column(name, definition)
  ddl('ALTER TABLE `%s` ADD COLUMN `%s` %s' % [@copy, name, definition])
end

#add_index(column_names, opts = {}) ⇒ Object

Raises:

  • (ArgumentError) 


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# File 'lib/zdm.rb', line 144

def add_index(column_names, opts = {})
  column_names = Array(column_names)
  index_name = opts[:name] || "index_#{@origin}_on_#{column_names.join('_and_')}"
  raise ArgumentError, "Index name '#{index_name}' on table #{@origin} is too long" if index_name.length > 64
  index_type = opts[:type] || (opts[:unique] ? 'UNIQUE' : '')
  index_using = "USING #{opts[:using] || 'btree'}"
  index_columns = quoted_columns_for_index(column_names, opts).join(',')
  ddl("CREATE #{index_type} INDEX `#{index_name}` #{index_using} ON `#{@copy}` (#{index_columns})")
end

#alter(definition) ⇒ Object 



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# File 'lib/zdm.rb', line 124

def alter(definition)
  ddl('ALTER TABLE `%s` %s' % [@copy, definition])
end

#change_column(name, definition) ⇒ Object 



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# File 'lib/zdm.rb', line 132

def change_column(name, definition)
  ddl('ALTER TABLE `%s` MODIFY COLUMN `%s` %s' % [@copy, name, definition])
end

#ddl(statement) ⇒ Object 



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# File 'lib/zdm.rb', line 120

def ddl(statement)
  @statements << statement
end

#remove_column(name) ⇒ Object 



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# File 'lib/zdm.rb', line 136

def remove_column(name)
  ddl('ALTER TABLE `%s` DROP `%s`' % [@copy, name])
end

#remove_index(index_name) ⇒ Object 



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# File 'lib/zdm.rb', line 154

def remove_index(index_name)
  ddl("ALTER TABLE `#{@copy}` DROP INDEX `#{index_name}`")
end

#rename_column(old_name, new_name) ⇒ Object 



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# File 'lib/zdm.rb', line 140

def rename_column(old_name, new_name)
  raise "Unsupported: you must first run a migration adding the column `#{new_name}`, deploy the code live, then run another migration at a later time to remove the column `#{old_name}`"
end