You can change the location of the iMANEFSDB.SDF(suggestion database) file using the following registry key: 

Location

For 64-bit client:

HKEY_LOCAL_MACHINE\SOFTWARE\iManage\Work\10.0\WCS

Or,

For 32-bit client:

HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\iManage\Work\10.0\WCS

Type: REG_SZ
Name: WCSDB Path
Value: <path>—for example, C:\WCS\DBFilePath