General description
[Databases]

General descriptions of the EMCAL databases and their usage.

Here's a table of EMCAL calibration databases we currently have, corresponding to calibration data "flavours". The table columns are :

• Description : a short description of what this flavour is
• Class name : the C++ class used to represent objects of this flavour
• Object granularity : basically how many channels one object handles
• Pg table name : the name of the PostgreSQL table holding the flavour's data
• ASCII location : where the data is read from or written to when using ASCII data source/destination (see later on explanation on this in the DataManager plugins section)

By clicking on the class name, you'll be able to see which other class/module uses that calibration flavour.

Flavour name	Description	Class name	Object granularity	Pg table name	ASCII location
Gains	(relative) Gain values	emcGainFEM	1 per FEM	calibemcgains	DIR/Gains
HLRatios	High to Low gains values	emcHLRatioFEM	1 per FEM	calibemchlratios	DIR/HLRatio
Pedestals	Pedestal values, Run1 version (3 ped. per amu cell)	emcPedestalFEM	1 per FEM	calibemcpedestals	DIR/PEDESTAL
Pedestals5	Pedestal values, Run2 and up version (5 ped per amu cell)	emcPedestalFEM	1 per FEM	calibemcpedestals5	DIR/PEDESTAL
QAs	Quality & Assurance values	emcQAFEM	1 per FEM	calibemcqas	DIR/QA
LCTofs	Least-Count ToF values	emcLCTofFEM	1 per FEM	calibemclctofs	DIR/ToF
WalkTofs	Walk ToF values	emcWalkTofFEM	1 per FEM	calibemcwalktofs	DIR/ToF
TofT0Bs	ToF-T0 drift values	emcTofT0FEM	1 per FEM	calibemctoft0bs	DIR/ToF
IniCal	Absolute energy calibration	emcCalibrationData	1 per sector	calibemcgenericinical	DIR/IniCal
RejectList	List of towers known to be bad (offline determined)	emcRejectList	1 for whole EMCAL	calibemcrejectlist	DIR/RejectList
Tof SectorOffsets	Mean ToF offset per sector	emcCalibrationData	1 per sector	calibemctofsectoroffsets	DIR/ToF/[runnumber]

Please note that all the *FEM classes derive from the same base class, emcCalFEM.

The table below lists the calibrations that are either not part of the DataManager realm or that are no longer used (or both).

Pg table name	(probable)(past) usage
calibemctoft0s	Old calibration software (now uses calibemctoft0bs)/ToF
calibemcbbct0	???
calibemcdeltat0_sector
calibemcdeltat0_tower
calibemcescale_tower
calibemcescalerecal
calibemcgainsrecal	Empty database
calibemclaser
calibemcrejectlistrecal
calibemct0_sector	Was used to correct for tof-drift per sector during some runs (e.g. Run3)
calibemct0_tower	Was used to correct for tof-drift per tower during some runs (e.g. Run3)
calibemctacpeds	Old calibration software
calibemctofdt
calibemctofgain
calibemctoflcdt
calibemctoflcrun
calibemctofmom
calibemctofrun
calibemcvd_t0sector

Note:

In the Objectivity era, the db names had dots in there, e.g. calib.emc.gains, so in the code you'll still find them referenced that way sometimes. It's transparent for you, as the underlying software understands both conventions.

In the following, databases are referred to by the flavour name (e.g. Gains).

Different ways of accessing the EMCAL databases.

The various methods for accessing EMCAL databases are depicted in the figure below. Depending on what you would like to do, the preferred method might differ.

If you just need a quick browse (of either the raw content of the databases or just the validity ranges of the calibrations) or to upload things into the DB from ASCII files, please use the emcDB program.

If you need to get access to plain objects like emcGainFEM for instance, then the API defined by the emcCalibrationDataHelper is your best take.

Then, if you really want or need to, you can use the emcDataManager interface. This might be the case if you'd like to write some piece of code that computes calibration parameters and must then be able to write them into a database (typical of an OnlCal piece of code, for instance).

Last, if you are really forced to do it (but this should be the exception), you might want to bypass all those APIs and use pdbcal directly (or worse, find your way directly using ODBC...). But then you're on your own...

EMCAL databases access routes