Development of DQM software infrastructure: storing and reading the monitoring information from the histograms filled by online client applications into relational tables.

In CMS the online DQM stores the monitoring information from several heterogeneous data sources into histograms, which are later sent to the DQMGUI for visualization. System for the handling of monitoring data is crucial for operating the detector and realizing whether or not it is undergoing failures: in particular, relational databases are the current best option for hosting such data. In this context a new DQM plugin DQMDatabaseWriter was developed, it provides interface which can be used in other DQM modules to drop desired data into the relational database. In addition, a python script provides possibility to read and visualize already saved records.