Compression ratio, Viewing compressed data, Compression ratio viewing compressed data – Rockwell Automation RSBizWare Administration Guide User Manual

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Data compression Appendix C

and compressed into a block of data that is then inserted into the
database as a single record.

The following user-readable summary information is included with
the block of data:

• An internal data point identifier.
• The time range covered by the compressed data.
• The maximum and minimum data point samples that were

collected.

• The number of data point samples that make up the

compressed record.

• The number of samples (if any) collected with bad OPC

quality.

Your individual compression ratio will vary based on several factors,

including the nature of the data being collected and transaction
parameters such as block size, sample rate, and signal type. For
example, steady state data will yield a higher compression factor than
random data. For this reason, it can be difficult to exactly predict the
compression ratio that you will realize.

The following compression ratios were observed based on system
testing with data point samples collected once a second, and with a
block size of 256:

Signal type

Compression ratio

Steady State

15:1

Saw Tooth

7:1

Random

3:1

Compressed data can be graphed and viewed easily using time-series

report objects in an RSBizWare report. Depending on the time

Compression ratio

Viewing compressed data

Rockwell Automation Publication BZWARE-IN001M-EN-P-June 2014

271

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