Thunderstone Search Appliance Manual

Update vs. Replace

The import process follows the currently-set Rewalk Type (here) mode. Thus, if the rewalk type is set to New, the import will start with a new (empty) database, import the file(s) into it, and use it to replace the existing search database upon completion. If the rewalk type is Refresh, the import will preserve the existing database, updating items when primary keys match, and adding new items when primary keys are new/distinct from the database. As a reminder of which action will be taken, a description is given at the top of the file-to-profile mapping form, e.g. "About to start replacing entire database with primary key ..." for a New type import.

When the rewalk type is Refresh, an additional Set To option is available for each profile field: ---Unchanged--. If this value is selected, the profile field will not be modified during the update. This can be used to update only certain fields during an import, without having to create a data file that specifies all the other fields as well. For example, a profile with SKU, Price, Color and Size fields (with primary key SKU) can have just its Price field updated, via a data file that need only contain SKU and Price columns (and rewalk type set to Refresh). All other columns (Color, Size etc.) will remain unmodified. Note: When an import is run that has any fields Set To ---Unchanged--, then any item in the imported file(s) that does not already occur in the database will be considered an import error: new rows cannot be inserted because some of the profile fields are undefined.