JDO-712 - SEQUENCE/SCHEMA default names

[Tilmann Zäschke <ti...@gmx.de>]

Hi,

After the last telecon (that I attended) I had a look at various DBMS
for their handing of SEQUENCEs and schema
spaces.

If I remember correctly, the question in the telecon was to see which
DBMS support schema names for sequences.
I am a bit unclear now how this relates to the ticket, anyway, here is
what I found:

Postgres, Oracle and SQL Server allow creating sequences with optional
schema name: [schema_name.]sequence_name
MariaDB and DB2 do not appear to support schema names for sequences.
MySQL ans SQLite do not appear to support named sequences.

Some Object DBMS (such as ObjectDB) support named sequences via JPA
(@GeneratedValue/@SequenceGenerator).
As I understand, there is no way to create/use sequences without
attaching them to a Java field (=column in a table), so they are
implicitly bound to a table/schema.

No-SQL databases such as MongoDB, CouchDB or Cassandra do not really
support sequences as such, ie they clearly discourage their use even if
suported.

Also, DataNucleus:
http://www.datanucleus.org/products/datanucleus/jdo/mapping.html#valuegen_sequence


There seems to be no standard naming convention, except that the schema
name, if present, is separated by a '.' from from the sequence name.

Ticket: https://issues.apache.org/jira/browse/JDO-712

Kind regards,

Til