This section provides information about known issues with and design limitations of the Memcache API for MySQL Cluster.

Problems with AUTO_INCREMENT.  ndbmemcache bypasses the NDB storage engine's mechanism for handling AUTO_INCREMENT columns. This means that, when you insert rows using ndbmemcache into a table having an AUTO_INCREMENT column, this column is not automatically updated. This can lead to duplicate key errors when inserts are performed later using SQL in a MySQL client application such as mysql.

To work around this issue, you can employ a sequence generator as described here.