Convert Files from DAT to DATA¶

Overview & comparison of file types¶

AIMMS 3.0 stores cases were in so-called “data manager files”. AIMMS 3.12 introduced the .data format as an alternative.

This change was made for several reasons.

  • Data manager files (.dat) became difficult to manage when maintaining several cases.

  • Case files (.data) avoid the risk of data corruption in one case affecting other cases stored in the same file.

  • Storing multiple case files in a folder makes it easy to copy cases from multiple users in the same folder, and compare scenarios. (See the AIMMS User’s Guide, Section “Managing multiple case selections”.)

In projects created with AIMMS version before 3.14, a single data manager file (.dat) contains zero, one or more cases. From AIMMS version 3.14, a case file (.data) only stores one case, but multiple cases may be stored in the same folder.

Before AIMMS 3

AIMMS 3.14 and later

.dat

.data

Single data manager file contains zero, one or more cases

Disk files and folders store multiple files, with one case per file

The default location of .data files, is the data subfolder of the project folder. (You can modify this with the project option Default data folder.)

Upgrading an AIMMS project to a newer AIMMS release¶

When upgrading AIMMS on a particular project, the data management style persists. In other words, using AIMMS 3.12 on a project created using AIMMS 3.11, will still use as “data management style”: “Single data manager file”. This allowed users to use their data in data manager files created with older versions of AIMMS.

For these upgraded projects, the data management style can be changed; it is a setting of the project:

../../_images/SwitchDataManagementStyle.png

After changing this setting; AIMMS needs to be closed and re-opened before the change takes effect properly. (Just closing and re-opening the project is not sufficient).

After restarting AIMMS, the cases in data manager files can be extracted, by the dialog opened via:

../../_images/OpeningDataFile.png

but it now looks different:

../../_images/ConvertingDatToData.png

Converting procedure calls¶

The case and other data management procedures are not just renamed, they also collect identifiers to be stored in a different way:

  1. The Disk files and folders interface works with

    1. CaseTypes and

    2. Data categories.

    A case type may include data categories.

    More information about these data types can be found in the User Guide of AIMMS 3.

  2. The Disk files and folders interface works with subsets of AllIdentifiers, called CaseContentTypes.

    A union of two sets results in a new set. Thus CaseContentTypes are at least as generic as CaseTypes.

The API for working on cases is changed by changing from Single data manager file to Disk files and folders.

The functionality of the procedures in the column of the left is roughly, but not exactly, the same as the functionality offered by the procedures in the column on the left in the following table:

Single data manager file

Disk files and folders

CaseNew

CaseCommandNew

CaseFind

CaseFileURLtoElement

CaseLoadCurrent

CaseCommandLoadAsActive

CaseMerge

CaseCommandMergeIntoActive

CaseLoadCurrent

CaseCommandLoadAsActive

CaseLoadIntoCurrent

CaseCommandLoadIntoActive

CaseReadFromSingleFile

CaseFileLoad

CaseWriteToSingleFile

CaseFileSave

CaseSelect

CaseDialogSelectForLoad or CaseDialogSelectForSave

CaseGetCurrent

ActiveCaseFile

CaseSetCurrent

CaseFileSetActive

CaseSave

CaseCommandSave or CaseFileSave

CaseSaveAll

CaseDialogConfirmAndSave and CaseCommandSave

CaseSaveAs

CaseCommandSaveAs

CaseSelectMultiple

CaseDialogSelectMultiple

CaseGetChangedStatus

DataChangeMonitorHasChanged

CaseSetChangedStatus

DataChangeMonitorCreate or DataChangeMonitorReset

CaseGetType

CaseFileGetContents

As Data categories, Case Types, Data sets, and Data manager file are no longer relevant when working with Disk files and folders; the corresponding API’s are not supported with this option setting.