Module: Simple::SQL::SimpleTransactions

Included in:
Connection::PgConnection
Defined in:
lib/simple/sql/simple_transactions.rb

Overview

private

Instance Method Summary collapse

Instance Method Details

#transaction(&_block) ⇒ Object 



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# File 'lib/simple/sql/simple_transactions.rb', line 14

def transaction(&_block)
  # Notes: by using "ensure" (as opposed to rescue) we are rolling back
  # both when an exception was raised and when a value was thrown. This
  # also means we have to track whether or not to rollback. i.e. do roll
  # back when we yielded to &block but not otherwise.
  #
  # Also the transaction support is a bit limited: you cannot rollback.
  # Rolling back from inside a nested transaction would require SAVEPOINT
  # support; without the code is simpler at least :)

  if tx_nesting_level == 0
    exec "BEGIN"
    tx_started = true
  end

  self.tx_nesting_level += 1

  return_value = yield

  # Only commit if we started a transaction here.
  if tx_started
    exec "COMMIT"
    tx_committed = true
  end

  return_value
ensure
  self.tx_nesting_level -= 1
  if tx_started && !tx_committed
    exec "ROLLBACK"
  end
end

#tx_nesting_level ⇒ Object 



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# File 'lib/simple/sql/simple_transactions.rb', line 6

def tx_nesting_level
  @tx_nesting_level ||= 0
end

#tx_nesting_level=(tx_nesting_level) ⇒ Object 



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# File 'lib/simple/sql/simple_transactions.rb', line 10

def tx_nesting_level=(tx_nesting_level)
  @tx_nesting_level = tx_nesting_level
end