Google Search Appliance Creating the Search Experience - Manual (Page 48)

Google Search Appliance: Creating the Search Experience Best Practices 48
There is no limit to the number of attributes that you can configure in dynamic navigation. However,
adding more attributes might affect search latency. The maximum number of results returned per
attribute is 5000.
Also, for any configuration, you can enable dynamic navigation for secure search. With secure search,
dynamic navigation only includes documents that the user is authorized to see. For more information,
see “Dynamic Navigation for Secure Search” on page 48. You can also configure the search appliance to
automatically expand configured dynamic navigation attributes to include other terms. For more
information, see “Configuring Query Expansion for Dynamic Navigation” on page 50.
Dynamic Navigation for Secure Search
With dynamic navigation for secure search, the search appliance only uses documents that the user is
authorized to see to generate navigation options. Only attributes and values that are in the accessible
documents appear in the options and the counts include only the accessible documents.
To use dynamic navigation for secure search, enable it for a configuration and select one of the
following authorization modes:
• “Fast Authorization Mode” on page 48
• “All Authorization Mode” on page 48
For information about how to enable dynamic navigation for secure search, see “Creating a
Configuration and Adding Attributes” on page 49.
Fast Authorization Mode
In fast authorization mode, the search appliance only performs authorization based on Access Control
Lists (ACLs) and checks results that are
already available in cache to generate dynamic navigation options. It ignores documents that require
real-time authorization. If the search appliance ignores some documents, it indicates this with a greater
than sign (>) in the count that appears with the dynamic navigation options.
Google recommends using fast authorization mode, which is the default mode.
All Authorization Mode
In all authorization mode, the search appliance uses all types of authorization methods to generate
dynamic navigation options. If ACLs are not the primary method of authorization, users might receive
query timeout errors (500) when performing searches. If this happens, you might consider using fast
authorization mode instead.
Google recommends using all authorization mode only under the following conditions:
• Real-time authorization on the content server is fast.
• Only 3-5% of the documents in the corpus need real-time checks.
• The rest of the documents in the corpus use ACLs for authorization.