Indexing UNICOM Intelligence Data Files
Starting with UNICOM Intelligence Data Model 5.6, the UNICOM Intelligence Data File CDSC supports indexing on specific columns. Indexing significantly speeds up the selection, update, and deletion of statements when indexed columns are used in filter expressions.
Indexes can be added to top level mtText, mtLong, mtDouble , mtBool and mtDate columns. Whether the index will be created or removed is controlled by the custom property Index on the corresponding field in the Metadata Document. The context can be either Analysis or Question. When the Index custom property is set to True, the corresponding column will be indexed; when the Index custom property set to False the corresponding column’s index will be removed. The Respondent.Serial column is typically used to uniquely identify a respondent record, and is indexed by default (the column index can be explicitly removed by setting the Index custom property to False).
The indexes are not created immediately, and are created under the following scenarios:
▪A WHERE expression was natively evaluated in the UNICOM Intelligence Data File DSC and there were no created indexes. For more information, see
Natively supported WHERE expressions.
The custom property
Index controls whether the index is created or removed on the corresponding Metadata Document field. For more information, see
Custom properties in use in UNICOM Intelligence products.
See also