ConditionsData

Introduction

In Mu2e it will eventually be necessary to maintain a database of "calibration constants". This will include information like the measuured corrections to the nominal geometry, the gas gain in straws, the time-space relationship for the straws, the gain of the photosensors, the calibration curve for ADC's and so on. This sort of data was traditionally referred to as "calibration constants" or, simply, as "constants".

Many of the calibration constants, however, are actually time dependent, which leads to the tired joke that "constants aren't". In the interests of ridding the field of bad jokes, modern usage is that this sort of data is known as "conditions data".

Using the conditions database

selecting a calibration set

When accessing the conditions database, you select a purpose, such as "PRODUCTION" and version, such a "V1_1". These are entered in the DbService services stanza.

services : {
   DbService : {
      purpose :  PRODUCTION
      version :  v1_1
      dbName : "mu2e_conditions_prd"
      textFile : ["table.txt"]
      verbose : 1
   }
}

The version numbers have three fields like v1_2_3:

• major version number, this changes when there is a major change in the content of the calibration set, that a user should probably be aware of, such as going from unaligned data to aligned data. The modules and services that will run and their configuration are likely to change. Your physics results will probably change.
• minor version number. This changes when the list of table types changes, or if there was a repair to the calibration set. The modules and services that will run and their configuration might change. Your physics results might change.
• extension number. This changes when new runs are added to the calibration set - physics results do not change.

You need to provide a PURPOSE. If you have no interest in the version number, then you can leave it blank and the code will take the latest available. If you specify only the major version number, then the highest available minor version number will be used. Your results might change between runs of your exe. If you provide the major and minor version numbers, then any run numbers that successfully ran before will always run the same way, but runs that previously failed because no calibrations were available might succeed at a later time due to an extension of the calibration set. This (specifying major and minor) is probably the right approach for most user work. Finally, if you specify the major, minor and extension number, then you will get the exact same result every time.

The database parameter should usually be mu2e_condition_prd, and this is the default.

The table parameter allows you to add a table to the calibration set for testing, see below.

overriding a table with a local file

The conditions code allows a user to provide a file (or several files) with the effect that the file contents overrides or extends whatever is in the database.

The text file must have the following format:

TABLE <tableName> <IOV>
row1-col1, row1-col2, row1-col3
row2-col1, row2-col2, row2-col3
...

For example:

# my comment
TABLE TstCalib1 1001:2-1002
1,20,20.21
2,21,20.22
3,22,20.23

The table name is the same as the c++ class name. The IOV may be missing, in which case the table applies to all data. You can see the format of the IOV text here. The data is one line for each row. The rows may need to be in a specific order, depending on how it is coded and accessed. The columns are separated by commas, please see here for details on string columns. There may be several tables in one file.

Conditions data maintenance

During data-taking the detector experts responsible for calibrations will need to continually update the database with calibrations for the new data. This section explains their procedures.

permissions and roles

The current (10/2018) permissions. Access to write to the database is allowed by a kerberos ticket. When a username is recorded in the database, it is the account name, which is the same as the kerberos name.

Permissions	users
ADMIN_ROLE	gandr,kutschke,rlc
VAL_ROLE, MANAGER_ROLE	gandr,kutschke,rlc,brownd
TRK_ROLE, VAL_ROLE	brownd,rbonvent,edmonds
CAL_ROLE, VAL_ROLE	echenard,fcp
CRV_ROLE, VAL_ROLE	ehrlich,oksuzian

• ADMIN_ROLE owns all tables and has complete control. It can add or drop tables, and everything in between. Only a few experts will have this role. The only regular job will be to create new calibration tables.
• VAL_ROLE can make intervals of validity and make groups of IOVs. All detector calibrators will have this role.
• MANAGER_ROLE can commit to the higher-level interval of validity tables. This includes declaring a new calibration table, creating a new list of calibration tables, purposes, or versions of a purpose, and extend a calibration set. It is expected that only a few active offline production managers will have this role at any one time.
• TRK_ROLE can commit calibration data to tables with names Trk*, and similarly for the other detector roles. Only a few experts in each detector, with the responsibility to maintain calibrations, will have this role.

Committing an interval of validity

Intervals are inclusive, the end points stated are in the interval. You can't create an interval where the end is before the beginning, so all intervals contain at least one subrun.

String	Interpreted
EMPTY	0:0-0:0
MAX	0:0-999999:999999
ALL	0:0-999999:999999
1000	1000:0-1000:999999
1000-1000	1000:0-1000:999999
1000-MAX	1000:0-999999:999999
MIN-1000	0:0-1000:999999
MIN-MAX	0:0-999999:999999
1000-2000	1000:0-2000:999999
1000:10-2000	1000:10-2000:999999
1000:11-1001:23	1000:11-1001:23

strings

Arbitrary string input occurs at two places

1. when adding comments to a dbTool create action, such as creating a new purpose or version
2. when uploading a calibration table that has a string column

In general, there are three special characters to watch our for: double quotes, used for quoting ("), comma, used for column separation (,), and hash, used for comments (#).

When inputing a string to dbTool to include a comment, there are only two rules:

1. if more than one word, use double quotes
--comment "two words"
2. when using a double quote in a string, escape it
--comment "two \"words\""

When writing a file that contain calibration data, the following rules apply

1. comments may be included by writing the hash (#) as the first character of a line. Comments are not allowed embedded in lines with data. The hash may be used in a string column.
# this is a legal comment TABLE tableName1 1, 1.2 # legal comment # legal comment - first non-whitespace char is the hash 2, 1.1 # illegal comment - will crash on parse (part of number column) TABLE tableName2 1, 1.2, GOOD 2, 1.1, BAD # malformed comment - will appear in string column 3, 1.1, failed check #3 OK, legal to use hash in string
2. commas must be quoted
TABLE tableName2 1, 1.2, GOOD 2, 1.1, BAD, or not will crash on parse 3, 1.1, "BAD, or not" OK
3. embedded double quotes must escaped or doubled
TABLE tableName2 1, 1.2, GOOD OK 1, 1.2, "GOOD" OK 3, 1.1, really BAD OK, multiple words OK (as long as no commas or quotes) 3, 1.1, ain't really BAD OK, single quotes OK 2, 1.1, Joe says "BAD" OK 2, 1.1, Joe says "BAD, or not" OK, comma requires quotes 3, 1.1, "Joe says \"BAD\"" OK 4, 1.1, "Joe says ""BAD""" OK 4, 1.1, "Joe says "BAD"" will crash on parse 5, 1.1, "Joe says, ""BAD""" OK, comma requires quotes, embedded quotes must be escaped or doubled

Calibration set maintenance

During data-taking the database managers will need to continually update the database higher-level tables as calibrators enter new data. This section explains these procedures. This section assumes the reader is familiar with the ConditionsSchema.

The following are several procedures that will typically be needed.

Extend a calibration set

This is the most common procedure. At this point there exists a calibration set - a PURPOSE and VERSION. The VERSION here refers to the major and minor numbers, like v1_1. This procedure extends this set, so takes a new set of tables represented by a GROUP number (or numbers), given to you by calibrators, and extends the calibration set. For example, an extension might take calibration set PRODUCTION v1_1_10, adding some groups of tables, to create PRODUCTION v1_1_11.

dbTool commit-extension --purpose PRODUCTION --version v1_1 --gid 4

the result shows the new full version number with the new extension. --gid can take a list of numbers, or a file containing numbers (see the dbTool help). You can verify the calibration set with

dbTool print-set --purpose PRODUCTION --version v1_1 --details

once an extension is created it is permanent and can't be deleted or undone. If there is a mistake, the procedure is to create a new VERSION, copy over the correct part, then create a new correct extension.

Create a new version of a purpose

A new version of a PURPOSE is needed when either the types of tables included in this calibration set needs to change, or if there was a mistake in the contents of the set.

You will need a list of tables to include in this calibration set.

dbTool commit-version --purpose PRODUCTION --list 3 --major 1 --minor 3 --comment "fix run 1234 of version 1_2"

Create a new purpose

In this case you are creating a whole new purpose. This should be a rare procedure and would indicate a whole new procedure is being introduced, for example, CRV group wants to run a calibration job on new data and needs the nominal calibration as input to the job. They don't care about any other detector calibrations.

dbTool commit-purpose --name CRV_CALIBRATION --comment "input to the CRV calibration job"

the result can be checked with

dbTool print-purposes

this print shows the PID, which uniquely identifies this PURPOSE. Every PURPOSE must have a unique name.

Notes

• Art interface:
  • art talk on a db interface.
  • csv_qe_api query_engine wrapper and generic table (`upd list -aK+ csv_qe_api`)
• ConDB - urls access to REST server
  • ConDB Web Interface urls that return csv, assumes time IOV
• query_engine wiki - a generic query db url/REST interface
• Web Data Access (wda) manual (ups product) c function wrapper, takes urls, runs curl, returns pointer to memory, has utilities for converting csv to values.
  • nu products
• nutools - contains nova generic table
• nucond -
• MINOS DB manual
• UconDB unstructured DB

• 5/9/18 created dev conditions

psql -h ifdb04  -p 5444  mu2e_conditions_dev

• query engine

non-cached: http://dbdata0vm.fnal.gov:9090/QE/mu2e/dev/app/SQ/query?t=test
cached: http://dbdata0vm.fnal.gov:9091/QE/mu2e/dev/app/SQ/query?t=test

• setup postgresql v9_3_9
• hypernews mu2e-hn-ConditionsDB@listserv.fnal.gov

CREATE ROLE admin_role;
GRANT ALL to adm_role;
GRANT admin_role to gandr,kutschke,rlc;

CREATE ROLE trk_role;
GRANT trk_role TO brownd,rbonvent,edmonds;

CREATE ROLE cal_role;
GRANT cal_role TO echenard,fcp;

CREATE ROLE crv_role;
GRANT crv_role TO ehrlich,oksuzian;