Class: Foundries::Snapshot::Adapters::PostgresAdapter

Inherits:
Object
  • Object
show all
Defined in:
lib/foundries/snapshot/adapters/postgres_adapter.rb

Instance Method Summary collapse

Constructor Details

#initialize(connection) ⇒ PostgresAdapter

Returns a new instance of PostgresAdapter.



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# File 'lib/foundries/snapshot/adapters/postgres_adapter.rb', line 7

def initialize(connection)
  @connection = connection
end

Instance Method Details

#capture(table_name, io) ⇒ Object 



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# File 'lib/foundries/snapshot/adapters/postgres_adapter.rb', line 23

def capture(table_name, io)
  raw = @connection.raw_connection
  raw.copy_data("COPY #{quoted(table_name)} TO STDOUT") do
    while (row = raw.get_copy_data)
      io.write(row)
    end
  end
end

#count(table_name) ⇒ Object 



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# File 'lib/foundries/snapshot/adapters/postgres_adapter.rb', line 19

def count(table_name)
  @connection.select_value("SELECT COUNT(*) FROM #{quoted(table_name)}")
end

#disable_referential_integrity ⇒ Object 



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# File 'lib/foundries/snapshot/adapters/postgres_adapter.rb', line 41

def disable_referential_integrity
  @connection.execute("SET session_replication_role = replica")
  yield
ensure
  @connection.execute("SET session_replication_role = DEFAULT")
end

#empty?(table_name) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/foundries/snapshot/adapters/postgres_adapter.rb', line 15

def empty?(table_name)
  @connection.select_value("SELECT NOT EXISTS (SELECT 1 FROM #{quoted(table_name)})")
end

#reset_sequence(table_name) ⇒ Object 



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# File 'lib/foundries/snapshot/adapters/postgres_adapter.rb', line 48

def reset_sequence(table_name)
  pk = @connection.primary_key(table_name)
  return unless pk

  # Check for sequence first — UUID PKs have no sequence
  seq = @connection.select_value(
    "SELECT pg_get_serial_sequence(#{@connection.quote(table_name)}, #{@connection.quote(pk)})"
  )
  return unless seq

  max_id = @connection.select_value(
    "SELECT COALESCE(MAX(#{@connection.quote_column_name(pk)}), 0) FROM #{quoted(table_name)}"
  )
  @connection.execute("SELECT setval(#{@connection.quote(seq)}, #{max_id})")
end

#restore(table_name, io) ⇒ Object 



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# File 'lib/foundries/snapshot/adapters/postgres_adapter.rb', line 32

def restore(table_name, io)
  raw = @connection.raw_connection
  raw.copy_data("COPY #{quoted(table_name)} FROM STDIN") do
    io.each_line do |line|
      raw.put_copy_data(line)
    end
  end
end

#table_names ⇒ Object 



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# File 'lib/foundries/snapshot/adapters/postgres_adapter.rb', line 11

def table_names
  @connection.tables - %w[schema_migrations ar_internal_metadata]
end