From the post:
Neo4j 2.1.5 is a maintenance release, with critical improvements.
Notably, this release addresses the following:
- Corrects a Cypher compiler error introduced only in Neo4j 2.1.4, which caused Cypher queries containing nested maps to fail type checking.
- Resolves a critical error, where discrete remove+add operations on properties could result in a new property being added, without the old property being correctly removed.
- Corrects an issue causing significantly degraded write performance in larger transactions.
- Improves memory use in Cypher queries containing OPTIONAL MATCH.
- Resolves an issue causing failed index lookups for some newly created integer properties.
- Fixes an issue which could cause excessive store growth in some clustered environments (Neo4j Enterprise).
- Adds additional metadata (label and ID) to node and relationship representations in JSON responses from the REST API.
- Resolves an issue with extraneous remove commands being added to the legacy auto-index transaction log.
- Resolves an issue preventing the lowest ID cluster member from successfully leaving and rejoining the cluster, in cases where it was not the master (Neo4j Enterprise).
All Neo4j 2.x users are recommended to upgrade to this release. Upgrading to Neo4j 2.1 requires a migration to the on-disk store and can not be reversed. Please ensure you have a valid backup before proceeding, then use on a test or staging server to understand any changed behaviors before going into production.
Neo4j 1.9 users may upgrade directly to this release, and are recommended to do so carefully. We strongly encourage verifying the syntax and validating all responses from your Cypher scripts, REST calls, and Java code before upgrading any production system. For information about upgrading from Neo4j 1.9, please see our Upgrading to Neo4j 2 FAQ.
Do you remember which software company had the “We are holding the gun but you decide whether to pull the trigger” type upgrade warning? There are so many legendary upgrade stories that it is hard to remember them all. Is there a collection of upgrade warnings and/or stories on the Net? Thanks!
BTW, if you are running Neo4j 2.x upgrade. No comment on Neo4j 1.9.