Writing to a Quantum file

Quantum DSC can write response (case) data into a Quantum-format ASCII file based on card, column, and punch information held in the questionnaire definition (.mdd) file. You can use the UNICOM Intelligence Data Model accessory, Metadata Model to Quantum, to set up the card, column, and punch information in the questionnaire definition.

Quantum DSC can also write out a basic Quantum specification based on the same card, column, and punch information. This means that Quantum DSC is now both a case data source component (CDSC) and a metadata source component (MDSC). For more information, see The Quantum specification.

Quantum DSC creates a .dat file that contains the response data in Quantum ASCII format. Depending on how the questionnaire definition and the data were set up, Quantum DSC may also create a .dau file (also known as the overflow file). This file contains responses to questions that need to be transcribed, coded, or checked. The responses can either be in the form of text or the name of a source file that records the response: for example, the name of a .tiff file that contains a scanned image of a handwritten response.

You can run Quantum DSC in validating or nonvalidating mode. When you run it in validating mode, you can choose:

▪Clean mode. Quantum DSC rejects any questionnaire items that have missing or inconsistent card or column details and any case data that does not conform to the card and column specifications in the questionnaire definition.

▪Dirty mode. Quantum DSC accepts many inconsistencies in the card and column specifications in the questionnaire definition and rejects response data only if it cannot be stored in the allocated columns without truncating it or overwriting other data. Quantum DSC issues a warning when accepting inconsistent data.

When you run Quantum DSC in nonvalidating mode, it performs no validity checks on the data. If the data is too big to fit in the allocated columns, it will overflow into the following columns and overwrite any data that has already been written to those columns, without issuing a warning. If subsequently data is written to the columns into which the data overflowed, Quantum DSC will overwrite the existing data without issuing a warning.

If the .dat or .dau files that Quantum DSC is to write to already exist, Quantum DSC appends new data to the files. Quantum DSC checks that the files are in a compatible format but does not read or check the data that they already contain in any way. You must therefore be careful not to create duplicate records by appending records with the same serial numbers as those that already exist.