## 1 Mnesia Release Notes

This document describes the changes made to the Mnesia system from version to version. The intention of this document is to list all incompatibilities as well as all enhancements and bugfixes for every release of Mnesia. Each release of Mnesia thus constitutes one section in this document. The title of each section is the version number of Mnesia.

### 1.1 Mnesia 4.4

#### 1.1.1 Fixed Bugs and Malfunctions

- Mnesia ignored the module argument to mnesia:restore/2. Thanks Paul Minerio.
  Own Id: OTP-6981

#### 1.1.2 Improvements and New Features

- Mnesia's snmp operations snmp_get_row/2, snmp_get_next_index/2 and snmp_get_mnesia_key/2 have been made context aware, i.e. inside a transaction they will compensate for table updates made in earlier in the same transaction. This might cause a performance drop if a lot of updates have been made before the invocation of these functions.
  *** POTENTIAL INCOMPATIBILITY ***
  Own Id: OTP-6856 Aux Id: seq10671
- Introduced erlang:phash/2 as new default for fragmented tables. Already existing tables will continue to use whatever hash function they where using.
  Own Id: OTP-6923
- Introduced mnesia:is_transaction/0.
  Own Id: OTP-6995 Aux Id: seq10812

#### 1.1.3 Known Bugs and Problems

- Rearranging fragmented tables is an O(N^2) operation.
  Own Id: OTP-6300

### 1.2 Previous Notes

For information about older versions see release notes history.

mnesia 4.4
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