Class: CassandraObject::Adapters::HstoreAdapter

Inherits:
AbstractAdapter show all
Defined in:
lib/cassandra_object/adapters/hstore_adapter.rb

Defined Under Namespace

Classes: QueryBuilder

Instance Attribute Summary

Attributes inherited from AbstractAdapter

#config

Instance Method Summary collapse

Methods inherited from AbstractAdapter

#batch, #batching?, #execute_batchable, #initialize

Constructor Details

This class inherits a constructor from CassandraObject::Adapters::AbstractAdapter

Instance Method Details

#connection ⇒ Object 



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# File 'lib/cassandra_object/adapters/hstore_adapter.rb', line 56

def connection
  # conf = {:adapter=>"postgresql", :encoding=>"unicode", :database=>"axle_place_test", :pool=>5, :username=>"postgres"}
  # @connection ||= ActiveRecord::Base.postgresql_connection(conf)
  ActiveRecord::Base.connection
end

#create_ids_where_clause(ids) ⇒ Object 



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# File 'lib/cassandra_object/adapters/hstore_adapter.rb', line 125

def create_ids_where_clause(ids)
  ids = ids.first if ids.is_a?(Array) && ids.one?

  if ids.is_a?(Array)
    id_list = ids.map { |id| quote(id) }.join(',')
    "#{primary_key_column} IN (#{id_list})"
  else
    "#{primary_key_column} = #{quote(ids)}"
  end
end

#create_table(table_name, options = {}) ⇒ Object 



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# File 'lib/cassandra_object/adapters/hstore_adapter.rb', line 116

def create_table(table_name, options = {})
  connection.execute 'CREATE EXTENSION IF NOT EXISTS hstore'
  ActiveRecord::Migration.create_table table_name, id: false do |t|
    t.string :id, null: false
    t.hstore :attribute_store, null: false
  end
  connection.execute "ALTER TABLE #{table_name} ADD CONSTRAINT #{table_name}_pkey PRIMARY KEY (id)"
end

#delete(table, ids) ⇒ Object 



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# File 'lib/cassandra_object/adapters/hstore_adapter.rb', line 100

def delete(table, ids)
  statement = "DELETE FROM #{table} WHERE #{create_ids_where_clause(ids)}"

  execute_batchable statement
end

#execute(statement) ⇒ Object 



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# File 'lib/cassandra_object/adapters/hstore_adapter.rb', line 62

def execute(statement)
  ActiveSupport::Notifications.instrument("cql.cassandra_object", cql: statement) do
    connection.exec_query statement
  end
end

#execute_batch(statements) ⇒ Object 



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# File 'lib/cassandra_object/adapters/hstore_adapter.rb', line 106

def execute_batch(statements)
  stmt = [
    "BEGIN",
    statements * ";\n",
    'COMMIT'
  ] * ";\n"

  execute stmt
end

#fields_to_postgres_array(fields) ⇒ Object 



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# File 'lib/cassandra_object/adapters/hstore_adapter.rb', line 140

def fields_to_postgres_array(fields)
  quoted_fields = fields.map { |field| "'#{field}'" }.join(',')
  "ARRAY[#{quoted_fields}]"
end

#insert(table, id, attributes) ⇒ Object 



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# File 'lib/cassandra_object/adapters/hstore_adapter.rb', line 76

def insert(table, id, attributes)
  not_nil_attributes = attributes.reject { |key, value| value.nil? }
  statement = "INSERT INTO #{table} (#{primary_key_column}, attribute_store) VALUES (#{quote(id)}, #{attributes_to_hstore(not_nil_attributes)})"
  execute_batchable statement
end

#primary_key_column ⇒ Object 



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# File 'lib/cassandra_object/adapters/hstore_adapter.rb', line 52

def primary_key_column
  'id'
end

#quote(value) ⇒ Object 



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# File 'lib/cassandra_object/adapters/hstore_adapter.rb', line 136

def quote(value)
  connection.quote(value)
end

#select(scope) ⇒ Object 



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# File 'lib/cassandra_object/adapters/hstore_adapter.rb', line 68

def select(scope)
  statement = QueryBuilder.new(self, scope).to_query

  connection.execute(statement).each do |attributes|
    yield attributes[primary_key_column], hstore_to_attributes(attributes['attribute_store'])
  end
end

#update(table, id, attributes) ⇒ Object 



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# File 'lib/cassandra_object/adapters/hstore_adapter.rb', line 82

def update(table, id, attributes)
  return if attributes.empty?

  not_nil_attributes = attributes.reject { |key, value| value.nil? }
  nil_attributes = attributes.select { |key, value| value.nil? }

  if not_nil_attributes.any? && nil_attributes.any?
    value_update = "(attribute_store - #{fields_to_postgres_array(nil_attributes.keys)}) || #{attributes_to_hstore(not_nil_attributes)}"
  elsif not_nil_attributes.any?
    value_update = "attribute_store || #{attributes_to_hstore(not_nil_attributes)}"
  elsif nil_attributes.any?
    value_update = "attribute_store - #{fields_to_postgres_array(nil_attributes.keys)}"
  end

  statement = "UPDATE #{table} SET attribute_store = #{value_update} WHERE #{primary_key_column} = #{quote(id)}"
  execute_batchable statement
end