CCDB 1.00

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CCDB 1.00 release notes

Creating tables right from file and information about files

It is usual situation when one already has text data file and want to create table to store the data. mktbl -f helps with this

> mktbl /test/haha -f python/tests/test_table.txt #my lonely comment
The command to create table: 

mktbl /test/haha -r 2 X Y Z #my lonely comment

Comments in file: 
Test assignment for software tests

Now one can copy it and run. It is not done automatically to be sure the values are reviewed.

The file is:

#Test assignment for software tests
#& X            Y            Z
  2.2          2.3          2.4         
  2.5          2.6          2.7     

You may notice that line with column names starts with #& while normal comments starts with plain #

One can use column types right there:

#& X=int            Y=int            NOT_Z=string

-f flag added to Info command also. info -f gives the info of text files, how CCDB sees it.

 ~/halld/ccdb/trunk $ ccdb info -f $CCDB_HOME/python/tests/test_table.txt
Rows: 2
Columns: 3
Column names:

Comments in file: 
Test assignment for software unit tests

Type 'ccdb mktbl -f /home/romanov/halld/ccdb/trunk/python/tests/test_table.txt' to see how to create a table for the file
Type 'ccdb add <table name> /home/romanov/halld/ccdb/trunk/python/tests/test_table.txt #<comments>' to add the file to existing table (rows and columns must consist)

'ls' command update

When ls is used directly on a table name, it gives data versions (as vers command):

 ccdb ls /test/test_vars/test_table
(ID)   (Created)              (Modified)              (variation)     (run range)      (comments)
 5      2012-10-30 23-48-43    2012-10-30 23-48-43     subtest         0-inf           Test assignment for 
 4      2012-10-30 23-48-42    2012-10-30 23-48-42     default         0-inf           Test assignment for 
 1      2012-07-30 23-48-42    2012-07-30 23-48-42     default         0-inf           Test assignment for 

-l flag adds info about table like (info) command.

ccdb ls -l /test/test_vars/test_table

The flags of ls command changed too:

Lists directories and tables for current directory

- Accepts wildcards symbols '*', and '?'

- When used on single table name, gives table data version as 'vers <table name>' command

    -v or --variations   - prints all variations
    -t or --tables       - prints full path for all tables
    -d or --directories  - prints all directories
    -x or --dtree        - draws directory tree

    -l or --extended     - shows extended info when is used on table


Users can use JAVA to access CCDB data. Or even Kotlin JVM language.

That is how it looks:

        JDBCProvider provider = CcdbPackage.createProvider("mysql://localhost")  ;
        Assignment asgmt = provider.getData("/test/test_vars/test_table");
        // gets data represented as number of columns
        for(Vector<String> row : asgmt.getStringTable()){
            for(String cell: row){
				System.out.print(cell + " ");
			System.out.println(); //next line after a row
        //gets some extended info about data

CCDB is provided as jar file including all required database drivers. The file could be found in:


C++ API update

Cell by cell readout and extended data inforation

In 0.9 users can read data like:

vector<vector<int> > tabledValues;
calib->GetCalib(tabledValues, "/test/test_vars/test_table2"));

So there is no extended information about the data, like column types or date. In CCDB 1.00 new GetAssignment function is introduced, which returns Assignment object. Assignment holds information about data and its type table. For example that is the way of getting columns information:

auto_ptr<Assignment> a(calib->GetAssignment("/test/test_vars/test_table"));    // auto_ptr to delete assignment after
                                                                               // auto_ptr is deprecated in C++11 btw

//Get type table and it holds information about columns 
const vector<ConstantsTypeColumn *> &columns = a->GetTypeTable()->GetColumns();

for(size_t i=0; i< columns.size(); i++)
    cout<<"   name: '"<< columns[i]->GetName() 
        <<"'  type: '"<< columns[i]->GetTypeString() <<"'"

But Assignment has even more handy feature. CCDB can have columns of different types in one table. For example: 2 columns of ints, 1 column of doubles and 1 column of strings (with some descriptions). There was no direct way to read it that way in 0.9. But with assignment you can do:

a->GetValueInt(0, 0)
a->GetValueInt(0, 1)
a->GetValueDouble(0, 2)
a->GetValue(0, 3)       //string

Or even better! If column names are "x", "y", "gain", "description" one can use

a->GetValue("description")       //string
//assuming row is 0. if it is not 0, one can use:
a->GetValueInt(101, "x")


CCDB now ships examples folder:


Where you can find some simple examples of how to use CCDB C++ user api. Add 'with-examples=true' flag to scons to compile the examples.

   scons with-examples=true

After the compilation examples can be run from console as example_ccdb_(example name)