Table of Contents

Database tags (CondDB and DDDb)

Data is produced or processed with different database tags. For example if the VELO was open, the database tag needs to specify that.

Find the correct tags for your data

Look at your datafiles from the bookkeeping: the file names contain the dataset number. For the following datafile the dataset number is 5630.

DATAFILE='LFN:/lhcb/MC/MC09/DST/00005630/0000/00005630_00000001_1.dst

To look up the tags log in to lxplus (you need a Grid Certificate to do this):

SetupProject LHCbDirac
dirac-bookkeeping-production-informations <datasetNumber>

for example:

dirac-bookkeeping-production-informations 5630

This produces the output:

Production Info: 
    Configuration Name: MC
    Configuration Version: MC09
    Event type: 30000000
Step0:Gauss-v37r5
      Option files: $APPCONFIGOPTS/Gauss/MC09-b450GeV-md100-nu1.py;$APPCONFIGOPTS/Conditions/MC09-20090602-vo-md100.py;$DECFILESROOT/options/30000000.opts;$LBPYTHIAROOT/options/Pythia.opts
      DDDb: MC09-20090602
      ConDDb: sim-20090402-vo-md100
Step1:Boole-v19r7
      Option files: $APPCONFIGOPTS/Boole/MC09-WithTruth.py;$APPCONFIGOPTS/Conditions/MC09-20090602-vo-md100.py
      DDDb: MC09-20090602
      ConDDb: sim-20090402-vo-md100
Step2:Brunel-v35r7
      Option files: $APPCONFIGOPTS/Brunel/MC09-WithTruth.py;$APPCONFIGOPTS/Conditions/MC09-20090602-vo-md100.py;$APPCONFIGOPTS/Brunel/veloOpen.py
      DDDb: MC09-20090602
      ConDDb: sim-20090402-vo-md100
Step3:LHCb-v28r0
      Option files: $STDOPTS/PoolCopy.opts
      DDDb: MC09-20090602
      ConDDb: sim-20090402-vo-md100
Number of Steps   1
Total number of files: 2
         LOG:1
         DST:1
Number of events [('DST', 53453)]
Path:  /MC/MC09/Beam450GeV-VeloOpen-MagDown-Nu1/MC09-Brunelv35-withTruth/None
/MC/MC09/Beam450GeV-VeloOpen-MagDown-Nu1/MC09-Brunelv35-withTruth/None/DST

Under the different steps you find the DDDb tags and the ConDDb tags, i.e. 'DDDb: MC09-20090602', 'ConDDb: sim-20090402-vo-md100' for the example file.

What if the tag returned is None?

It can happen, that the info reported by dirac-bookkeeping-production-informations lists None as database tags:

Production Info: 
    Configuration Name: MC
    Configuration Version: MC11a
    Event type: 11144103
-----------------------
 StepName: Merge12 for MC11 
    ApplicationName    : LHCb
    ApplicationVersion : v33r1
    OptionFiles        : $APPCONFIGOPTS/Merging/CopyDST.py
    DDB                : None
    CONDDB             : None
    ExtraPackages      : AppConfig.v3r118
-----------------------

In this case the production information got lost while merging. You can have a look at the database tags used for the merge job and hope they where correct

SetupGauss
cat $GAUSSROOT/options/Gauss-MC11a.py

Implement the tags in your options file

When using real data, you need a DDDB tag (DDDB) and a CondDB (LHCBCOND) tag.

Insert the following lines to your options file:

DaVinci().CondDBtag = "head-20091211"
DaVinci().DDDBtag = "head-20091120"

When running over Monte Carlo data, you need a DDDB tag (DDDB) and a CondDB (SIMCOND) tag.

DaVinci().CondDBtag = "sim-20090402-vo-md100"
DaVinci().DDDBtag = "MC09-20090602"
from Configurables import CondDB
CondDB(UseOracle = True)

Using dictionaries

You can find a file including dictionaries of all yet known (and at least often used) tags under: “/afs/cern.ch/user/e/elsasser/public/dbtags/tagdict.py” which can be imported to be used in a python script. The base file is located under “/afs/cern.ch/user/e/elsasser/public/dbtags/prodFileList.txt”

Check if the correct tags were used in your job

Look at the stdout file of your job: After the start of Loki you will find something like the following statements:

DDDB                 INFO Connected to database "sqlite_file:/afs/cern.ch/project/gd/apps/lhcb/lib/lhcb/DBASE/Det/SQLDDDB/v5r17/db/DDDB.db/DDDB"
DDDB                 INFO Using TAG "MC09-20090602"
SIMCOND              INFO Connected to database "sqlite_file:/afs/cern.ch/project/gd/apps/lhcb/lib/lhcb/DBASE/Det/SQLDDDB/v5r17/db/SIMCOND.db/SIMCOND"
SIMCOND              INFO Using TAG "MC09-20090402-vc-md100"

Where to find information about global tags

Follow this link: http://lhcb-release-area.web.cern.ch/LHCb-release-area/DOC/dbase/conddb/release_notes.xml

More

"Recommended Tags" Page in TWiki