Storing Waveforms

I am designing a new laboratory database. I want to store the raw results for all tests together. However, results can either be a single measurement or a raw waveform.
Which case below is ideal (and why)? ... or provide your own ideal option.
TEST
test_id*
(other TEST fields)
OPTION 1: Separate single values and waveform results
    TEST (1 -- many) MEASUREMENT
         ( \-- many) RAW_HEADER 1 -- many RAW_POINT
    MEASUREMENT             RAW_HEADER
      measurement_id*         raw_header_id*
      test_id (FK)            test_id (FK)
      rec_time as DATE        start_time as DATE
      measurement             sample_rate
                            RAW_POINT
                              raw_header_id* (FK)
                              point_index*
                              raw_measurement
OPTION 2: Overlap common fields from OPTION 1
    TEST (1 -- many) MEASUREMENT (1 -- many) RECORDING_POINTSame as OPTION 1 except:
    <tt>MEASUREMENT</tt>: <tt>measurement</tt> for signals is the sample_rate
    <tt>RAW_POINT</tt>: <tt>raw_header* (FK)</tt> changed to <tt>measurement_id* (FK)</tt>
    <tt>RAW_HEADER</tt>: not needed
OPTION 3: Encode signals into <tt>BLOB</tt>
    TEST (1 -- many) MEASUREMENT
    MEASUREMENT
      measurement_id*
      test_id (FK)
      rec_time as DATE
      measurement
      signal as BLOBFor a single value <tt>measurement</tt> is the measurement and <tt>signal</tt> is <tt>NULL</tt>
For signals <tt>measurement</tt> is the sample_rate and <tt>signal</tt> stores the encoded data points
Legend:
<li><tt>__*_ </tt> Fields followed by an asterisk are
the complete primary key.
<li><tt>(FK)</tt> Fields followed by <tt>(FK)</tt> indicate field has foreign key constraint.
<li><tt>____</tt> All fields are of type <tt>NUMBER</tt> unless otherwise specified.
FYI:
In my own opinion:
I like Option 1 because it separates the single values and signals. I could even add a raw_point_id and store the number of data points in the RAW_HEADER to access the data in both directions.
Option 2 which combines common fields to put everything in one place.
Concerning Option 3, and correct me if I'm wrong. It would be difficult for Oracle (rather than the program retrieving) to decode the raw data stored in the BLOB to use in other calculations
Edited by: StevenATK on Jun 29, 2009 3:20 PM

delete this edit.

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Ihsan wrote in message news:<[email protected]>...
> I'm trying to control tektronix AWG2021 using GPIB with labview, but
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Attachments:
Acquire_N_Scans_save_to_ss.vi ‏87 KB

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Sorry, this is the kind of thing that happens when you have been out for too long.
Message Edité par chilly charly le 10-22-2006 11:09 AM
Chilly Charly (aka CC)
E-List Master - Kudos glutton - Press the yellow button on the left...
Attachments:
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Attachments:
5124_update.vi ‏157 KB

Thank you so much for your reply, David. Let me try and explain my
situation and setup a little better, as well as discuss the points you
made in your reply. Beware, you may want to refill your coffee as this
post is long .
I am using an embedded controller in a PXI-1044 chassis. I now have the
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to the chassis over the network as I am also connected to the local
network. I have an oscilloscope next to me that takes as input the
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on the chassis? How can I connect to it to do drag and drop to get
saved waveform data off of it? This is the main problem I am now
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connected to the chassis, which assumes that I can have access to the
internal storage to tell it to save files to the external hard disk.
For now saving it to the internal hard disk is just fine until
everything is proven to work, but I would like to get the data off of
the internal hard drive to put on another computer.
Any answers/suggestions on my above questions are greatly appreciated.
I also want to thank you for reading this long post . I eagerly await
a reply. Thanks again in advance.
Chris
Attachments:
5124_update.vi ‏143 KB

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I'm pretty sure other people had my problem, but I don't know how to word it... and can't find a solution for it... Maybe I just don't understand Labview enough to know what's going on.
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Go to Solution.
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Save to spreadsheet.vi ‏17 KB

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This account is no longer active. Contact ShadesOfGray for current posts and information.
Attachments:
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