Class: Sequel::Postgres::PropertyGraph::Generator::Alter

Inherits:
Sequel::Postgres::PropertyGraph::Generator show all
Defined in:
lib/sequel/adapters/shared/postgres.rb

Overview

Alter is used to evaluate the block given to DatabaseMethods#alter_property_graph, used to specify changes to an existing property graph.

Constant Summary

Constants inherited from Sequel::Postgres::PropertyGraph::Generator

Vertex

Instance Method Summary collapse

Methods inherited from Sequel::Postgres::PropertyGraph::Generator

new

Constructor Details

#initialize(&block) ⇒ Alter

Returns a new instance of Alter.



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# File 'lib/sequel/adapters/shared/postgres.rb', line 527

def initialize(&block)
  @operations = []
  instance_exec(&block)

  @operations.each do |op|
    case op[:op]
    when :add_vertex_tables, :add_edge_tables
      op[:tables].freeze
    end
    op.freeze
  end
  @operations.freeze
  freeze
end

Instance Method Details

#add_edge(name, opts = OPTS, &block) ⇒ Object

Add an edge to the property graph, with the block used to configure the edge.

alter_property_graph.add_edge(:e){source :v1; destination :v2}
# ADD EDGE TABLES (e SOURCE v1 DESTINATION v2)


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# File 'lib/sequel/adapters/shared/postgres.rb', line 560

def add_edge(name, opts=OPTS, &block)
  add_tables_operation(:add_edge_tables) << Edge.new(name, opts, &block)
  nil
end

#add_vertex(name, opts = OPTS, &block) ⇒ Object

Add a vertex to the property graph, with the block used to configure the vertex.

alter_property_graph.add_vertex(:v)
# ADD VERTEX TABLES (v)


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# File 'lib/sequel/adapters/shared/postgres.rb', line 551

def add_vertex(name, opts=OPTS, &block)
  add_tables_operation(:add_vertex_tables) << Vertex.new(name, opts, &block)
  nil
end

#alter_edge_table(name, &block) ⇒ Object

Modify an existing edge table (referenced by its alias).

alter_property_graph.alter_edge_table(:e, properties: :none){drop_label :l}
# ALTER VERTEX TABLE e DROP LABEL l


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# File 'lib/sequel/adapters/shared/postgres.rb', line 600

def alter_edge_table(name, &block)
  @operations.concat(AlterElement.new(:edge, name, &block))
  nil
end

#alter_vertex_table(name, &block) ⇒ Object

Modify an existing vertex table (referenced by its alias).

alter_property_graph.alter_vertex_table(:v){add_label :l}
# ALTER VERTEX TABLE v ADD LABEL l PROPERTIES ALL COLUMNS


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# File 'lib/sequel/adapters/shared/postgres.rb', line 591

def alter_vertex_table(name, &block)
  @operations.concat(AlterElement.new(:vertex, name, &block))
  nil
end

#data ⇒ Object 



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# File 'lib/sequel/adapters/shared/postgres.rb', line 542

def data
  @operations
end

#drop_edge_tables(aliases, opts = OPTS) ⇒ Object

Remove edge tables (referenced by their aliases) from the property graph. See #drop_vertex_tables.

alter_property_graph.drop_edge_tables([:e1, :e2])
# DROP EDGE TABLES (e1, e2)


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# File 'lib/sequel/adapters/shared/postgres.rb', line 582

def drop_edge_tables(aliases, opts=OPTS)
  @operations << {:op=>:drop_edge_tables, :aliases=>Array(aliases), :cascade=>opts[:cascade]}
  nil
end

#drop_vertex_tables(aliases, opts = OPTS) ⇒ Object

Remove vertex tables (referenced by their aliases) from the property graph. aliases can be a single alias or an array. Options: :cascade :: Use CASCADE instead of the default RESTRICT.

alter_property_graph.drop_vertex_tables([:v1, :v2])
# DROP VERTEX TABLES (v1, v2)


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# File 'lib/sequel/adapters/shared/postgres.rb', line 572

def drop_vertex_tables(aliases, opts=OPTS)
  @operations << {:op=>:drop_vertex_tables, :aliases=>Array(aliases), :cascade=>opts[:cascade]}
  nil
end

#set_owner(new_owner) ⇒ Object

Change the owner of the property graph. new_owner is usually a Symbol or SQL::Identifier for the role name, but can be Sequel.lit('CURRENT_USER') or Sequel.lit('SESSION_USER').

alter_property_graph.owner_to(:new_owner)
# OWNER TO new_owner


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# File 'lib/sequel/adapters/shared/postgres.rb', line 612

def set_owner(new_owner)
  @operations << {:op=>:set_owner, :owner=>new_owner}
  nil
end