This feature will be removed in a future version of Microsoft SQL Server. Avoid using this feature in new development work, and plan to modify applications that currently use this feature.
The IsFullTextKey property identifies the index used by Microsoft Search to support row identification.
If TRUE, the referenced index is used by Microsoft Search for row identification.
If FALSE, the referenced index is not used by Microsoft Search.
Microsoft Search requires that a single column identify rows participating in an index supporting full-text query. The column designated must contain unique, nonnull values and must participate in a PRIMARY KEY or UNIQUE key constraint. A table that contains a PRIMARY KEY constraint does not require a separate unique index for Microsoft Search configuration.
Use UniqueIndexForFullText to configure Microsoft Search full-text index key column use.