Overview:
There are two types of indexing schema, the default schema and the ItemGranularityOnly schema. The ItemGranularityOnly schema was introduced in Enterprise vault 6.0 to make searches more efficient. The ItemGranularityOnly schema is disabled by default in Enterprise Vault but can be enabled through a registry key on the Enterprise Vault Indexing server. The ItemGranularityOnly schema combines the information from attachments into the top level parent document in the index, so the attachments are not shown separately in the search. This means that Compliance Accelerator and Discovery Accelerator queries are faster but it also means that Browser search and Integrated search will return top level document results and not individual attachments when using the ItemGranularityOnly schema.  

Before deciding on whether or not to use ItemGranularityOnly, it should be noted the indexes must be rebuilt after the registry change has been made.  Rebuilding of large or numerous indexes would be a resource intensive undertaking and a decision weighing the advantages versus the disadvantages must be made.  How long does it take to rebuild an index?  How many indexes need to be rebuilt?  In the case of Optical Platter storage, the overhead of an index rebuild is very costly and is not recommended in a multiple platter environment without a large enough cache to accommodate the entire Vault Store of the indexes being rebuilt.

Before the registry change is made, Search.asp shows each attachment and inserted JPG's as a separate item and not part of the top level document. (Figure 1)

Figure 1
 

After the registry change all items that pertain to a certain archive item are combined within the top level document.  Notice the Items found is lowered from 16 to 3 and the attachments and JPG information is no longer visible. (Figure 2)

Figure 2
 


Resolution:
Note: Implementing the ItemGranularityOnly schema will require a rebuild of the index before it will take effect.

Warning: Incorrect use of the Windows registry editor may prevent the operating system from functioning properly. Great care should be taken when making changes to a Windows registry. Registry modifications should only be carried-out by persons experienced in the use of the registry editor application. It is recommended that a complete backup of the registry and workstation be made prior to making any registry changes.

1. On the Enterprise Vault Indexing server, create the following key with the Windows registry:

Key:   HKEY_LOCAL_MACHINE\SOFTWARE\KVS\Enterprise Vault\Indexing
Value Name:  SchemaType
Type:  DWORD
Value: 1

2. Restart the Enterprise Vault Indexing Service.

3. Rebuild the index.

Rebuild the index using IndexVolumeReplay.exe for Enterprise Vault 6.x and 7.x. (See the Related Documents section, article 287649)

Right-click the target archive and click Properties. The Advanced tab has the Rebuild Index button that will rebuild all the index volumes at once. (See the Related Documents section, article 292420)

4. To confirm the index has been rebuilt with the new ItemGranularityOnly schema run the following command:

IndexServer.exe /Summary <path to index files>

Example:

IndexServer.exe /Summary  D:\Index\index4\10F4642E7F3436343A958760052D63BD71110000EVSERVER

Review the SchemaFlags value in the summary report file
3 - ItemGranularityOnly schema is enabled
2 - Enterprise Vault 6.0 index without ItemGranularityOnly schema
1 - Enterprise Vault 5.0 index without ItemGranularityOnly schema