The package Database/AthenaPOOL/AthenaPoolExample contains running examples of algorithms writing and reading Data Objects using AthenaPool. This sub package, AthenaPoolExampleAlgorithms, defines the algorithms write and read data, tags and conditions via AthenaPOOL.

WriteData: The WriteData algorithm creates some ExampleHits in a ExampleHitContainer and records them into StoreGate.

WriteTag: The WriteTag algorithm creates an AthenaAttributeList and records it in StoreGate so it can be used for collections.

AthenaPoolExample_WriteJobOptions.py: These jobOptions create two streams to write two different data files via AthenaPOOL.

Tests:

- Simple Writing of EventData and InFile MetaData.
- Multiple Streams.
- Tag Writing.

run > checkFile.py SimplePoolFile1.root
## opening file [SimplePoolFile1.root]...
## importing ROOT...
## importing ROOT... [DONE]
## opening file [OK]
File:SimplePoolFile1.root
Size:       34.836 kb
Nbr Events: 20

================================================================================
     Mem Size       Disk Size        Size/Evt      MissZip/Mem  items  (X) Container Name (X=Tree|Branch)
================================================================================
      72.382 kb        0.000 kb        0.000 kb        1.000       20  (T) DataHeader
--------------------------------------------------------------------------------
      46.367 kb        0.000 kb        0.000 kb        1.000       20  (B) EventInfo_p2_McEventInfo
      29.958 kb        0.000 kb        0.000 kb        1.000       20  (B) ExampleHitContainer_p1_MyHits
       9.207 kb        0.000 kb        0.000 kb        1.000        1  (B) EventStreamInfo_p1_Stream1
      50.704 kb        0.000 kb        0.000 kb        1.000        1  (T) MetaDataHdrDataHeader
================================================================================
     208.618 kb        0.000 kb        0.000 kb        0.000       20  TOTAL (POOL containers)
================================================================================
## Bye.
run > checkFile.py SimplePoolFile2.root
## opening file [SimplePoolFile2.root]...
## importing ROOT...
## importing ROOT... [DONE]
## opening file [OK]
File:SimplePoolFile2.root
Size:       29.271 kb
Nbr Events: 20

================================================================================
     Mem Size       Disk Size        Size/Evt      MissZip/Mem  items  (X) Container Name (X=Tree|Branch)
================================================================================
      67.502 kb        0.000 kb        0.000 kb        1.000       20  (T) DataHeader
--------------------------------------------------------------------------------
      46.367 kb        0.000 kb        0.000 kb        1.000       20  (B) EventInfo_p2_McEventInfo
       9.207 kb        0.000 kb        0.000 kb        1.000        1  (B) EventStreamInfo_p1_Stream2
      50.704 kb        0.000 kb        0.000 kb        1.000        1  (T) MetaDataHdrDataHeader
================================================================================
     173.780 kb        0.000 kb        0.000 kb        0.000       20  TOTAL (POOL containers)
================================================================================
## Bye.

AthenaPoolExample_AppendJobOptions.py: These jobOptions appends events and tags to the second stream written by AthenaPoolExample_WriteJobOptions.py.

    Tests:

    - Simple Appending of EventData and InFile MetaData.
    - Tag Writing in update (append) mode.

Note:
- Appending InFile MetaData does _not_ work in the current framework.

run > checkFile.py SimplePoolFile2.root
## opening file [SimplePoolFile2.root]...
## importing ROOT...
## importing ROOT... [DONE]
## opening file [OK]
File:SimplePoolFile2.root
Size:       43.342 kb
Nbr Events: 40

================================================================================
     Mem Size       Disk Size        Size/Evt      MissZip/Mem  items  (X) Container Name (X=Tree|Branch)
================================================================================
      84.822 kb        0.000 kb        0.000 kb        1.000       40  (T) DataHeader
--------------------------------------------------------------------------------
      52.327 kb        0.000 kb        0.000 kb        1.000       40  (B) EventInfo_p2_McEventInfo
       9.207 kb        0.000 kb        0.000 kb        1.000        1  (B) EventStreamInfo_p1_Stream2
       9.207 kb        0.000 kb        0.000 kb        1.000        1  (B) EventStreamInfo_p1_Stream1
      51.562 kb        0.000 kb        0.000 kb        1.000        2  (T) MetaDataHdrDataHeader
================================================================================
     207.125 kb        0.000 kb        0.000 kb        0.000       40  TOTAL (POOL containers)
================================================================================
## Bye.

AthenaPoolExample_RWJobOptions.py: These jobOptions read the previous events (SimplePoolFile1.root from AthenaPoolExample_WriteJobOptions.py) and processes the hits into tracks which are than written out.

    Tests:

    - Reading of EventData (without navigation) and InFile MetaData.
- Writing EventData with navigational relations (ElementLinks, ElementLinkVector, Navigable) to
  upstream EventData.

run > checkFile.py SimplePoolFile3.root
## opening file [SimplePoolFile3.root]...
## importing ROOT...
## importing ROOT... [DONE]
## opening file [OK]
File:SimplePoolFile3.root
Size:       39.700 kb
Nbr Events: 20

================================================================================
     Mem Size       Disk Size        Size/Evt      MissZip/Mem  items  (X) Container Name (X=Tree|Branch)
================================================================================
      79.462 kb        0.000 kb        0.000 kb        1.000       20  (T) DataHeader
--------------------------------------------------------------------------------
      46.367 kb        0.000 kb        0.000 kb        1.000       20  (B) EventInfo_p2_McEventInfo
      49.346 kb        0.000 kb        0.000 kb        1.000       20  (B) ExampleTrackContainer_p1_MyTracks
       9.207 kb        0.000 kb        0.000 kb        1.000        1  (B) EventStreamInfo_p1_Stream1
      50.704 kb        0.000 kb        0.000 kb        1.000        1  (T) MetaDataHdrDataHeader
================================================================================
     235.086 kb        0.000 kb        0.000 kb        0.000       20  TOTAL (POOL containers)
================================================================================
## Bye.

AthenaPoolExample_ReadJobOptions.py: These jobOptions read the previous events (SimplePoolFile1-3.root).

    Tests:

    - Reading of EventData (with navigation) and InFile MetaData.
- Skipping events.

SimplePoolFile1.root: EventInfo, Hits SimplePoolFile2.root: EventInfo SimplePoolFile3.root: EventInfo, Hits (via Navigation), Tracks

Additional Documentation

See the ATLAS User/Developer HowTo document for additional information.

The code can be browsed using LXR (http://alxr.usatlas.bnl.gov/lxr/source/atlas/Database/AthenaPOOL/AthenaPoolExample/AthenaPoolExampleAlgorithms/)

Author

Peter van Gemmeren gemme.nosp@m.ren@.nosp@m.anl.g.nosp@m.ov