Changes to RDB-archive support
==============================

Date and associated version of SNS CSS

** 2011-11-??, 3.? **
1) BLOB support.
Waveforms used to be stored element-by-element in a array_val
table, which was very portable but inefficient.
Now a BLOB column in the sample table holds waveform data.
A configuration parameter allows use of either
the new BLOB or the old array_val table:

org.csstudio.archive.rdb/use_array_blob=(true|false)

2) Preference cleanup
After the archive plugin reorganization, the settings for
url, user, password, schema
could be set as preferences of the plugin org.csstudio.archive.rdb
and they could _also_ be set as preferences of the plugin
org.csstudio.archive.reader.rdb.
The latter had the highest precedence for the reader,
and the preference GUI in fact _only_ displayed the ...reader.rdb
settings, not the fall-back in ...archive.rdb that was
used when the ...reader.rdb settings were left empty.

Now each settings is associated with only one plugin,
and the preference GUI always shows the effective settings:

# Settings for all RDB archive plugins (read, write, config)
org.csstudio.archive.rdb/url
org.csstudio.archive.rdb/user
org.csstudio.archive.rdb/password
org.csstudio.archive.rdb/schema
org.csstudio.archive.rdb/use_array_blob

# Additional setting that only applies to the reader
org.csstudio.archive.reader.rdb/use_stored_procedure

Existing plugin_customization.ini files that used
...reader.rdb to set url, user, password, schema
need to be updated to use ...archive.rdb!


** 2011-06-13, 3.0.1 **
1) Archive plugin reorganization
The archive plugins, especially the engine code, was rearranged.
These plugins now contain the engine and API for reading or
writing archived data:

org.csstudio.archive.engine
org.csstudio.archive.config
org.csstudio.archive.writer
org.csstudio.archive.reader

These plugins contain the RDB-based implementation:

org.csstudio.archive.rdb
org.csstudio.archive.config.rdb
org.csstudio.archive.writer.rdb
org.csstudio.archive.reader.rdb

This should make it easier to provide for
example a Hypertable-based implementation of the
data store.

Eclipse preferences are set via combination of 
org.csstudio.archive.rdb and
org.csstudio.archive.reader.rdb.

** 2010-11-15, 2.5.0 **
1) PostgreSQL support
.. provided by ITER.


** 2010-03-01, 1.1.0  **
1) Oracle stored procedure
SNS uses a stored procedure in Oracle to accelerate reading "optimized"
data. See org.csstudio.archive.reader.rdb/archive_reader.pls for code.
Only used if org.csstudio.archive.reader.rdb/use_stored_procedure is defined.


** 2009-July-02, 1.0.19 **
1) Initial version of RDB archive
SNS uses Oracle-based archive store.
Code also supports MySQL.
