Introduction
Metrohm OMNIS software uses a Microsoft SQL Express Database. This is a free version, which has a 10GB limit. All data from OMNIS such as operating procedures, methods, sample lists, determination data, etc. is stored in this single database.
When approaching the 10GB limit, the software will display a warning message that the database has grown to a critical level. While it is possible to "reset" the database back to 0GB, this process removes the operating procedures and other user data that would need to be exported and re-imported which is prohibitively tedious.
Therefore, the best practice is to archive samples.
Archiving Samples
When archiving a sample list, a warning appears:
Proceed by clicking "Archive" and then choose the target directory where the data will be archived. This process exports and then deletes the individual sample files (.OSIN file format) from the sample list. However, the sample list itself is retained. It is therefore advisable that the archive directory is created with the same or similar name to the sample list itself. This way you have a 1:1 relationship between the (now empty) sample list and the hard drive location of the archive. This is especially helpful because of the reverse process. In order to restore data, the sample list must be opened and samples imported according to the process described here.
Archiving can be planned as a task in Settings → Scheduler. This automatically archives samples at a defined interval.
The execution of multiple tasks at the same time and for the same samples is not supported. Metrohm recommends defining each task in such a way that it takes other samples into account.
If a task is deleted during its execution, the task is continued until it fails or is terminated. After deleting a task, wait until the scheduled extension time has elapsed before creating a new task for the same samples.
Additional Information
Since OMNIS uses a SQL database, it is also possible to use a larger database external to the software which is managed by the end-users IT support. This allows for data storage in excess of 10GB. The basic instructions for configuring such a database are available on the Metrohm Knowledge Base. Please contact Metrohm Technical Support for additional help.
It is not necessary to restore data to the sample list it came from originally. It can be restored to any sample list. The decision on what to archive, and how to configure sample lists is fully customizable by the user and any data management processes that may exist.
For instance, a user can create a sample list that is specific to a project. The sample list for the project can be archived and then restored back to the same sample list later if desired.
Alternatively, if users create a new sample list on a daily basis, you can use the search query function to select a range of samples with specific criteria like a date range. Search queries can't be archived, but they can be converted into a new sample list which in turn can be archived and the other sample lists deleted afterwards. There is a button in the search query view that enables creation of a new sample list:
Sample lists can be thought of like playlists in a music library. The individual sample runs exist within the entire library, but the sample list exists for easy access to functions like running samples, recalculating samples, exporting, archiving, etc. In this sense, samples and subsamples can be removed from sample lists, but not from the database permanently. Separate functions do exist to delete data permanently from all samples lists but we do not recommend doing this regularly.
There is no right or wrong way to utilize sample lists. We recommend following a natural order that suits your procedures rather than using a "one size fits all" approach. Some common ways of delineating sample data include by project, by date, by product, by analysis or by shift.
Feel free to contact Metrohm Technical Support for additional help about this topic. 'Submit a request' for further assistance from Metrohm Technical Support at support.metrohmusa.com.
Additional Support
If you encounter any issues or need additional help, please submit a support ticket through Metrohm Technical Support.
For additional training on any of these topics, explore our available Metrohm Titration Training courses or learn more about our Metrohm Custom Training options.