Split Nintex Content DB

Recommended approach to Nintex content database design is to have one to one relationship between a SharePoint site collection , SharePoint CDB, and Nintex content DB. This means that each SP site collection will have a dedicated SharePoint Content Database and a dedicated Nintex workflows Content database. if you didn’t set it up from the initial Nintex installation you may have all-inclusive database, one DB that contains all site collection NW_CDB (Nintex Workflows Content DataBase). to enable 1-1 mapping follow these steps:

  1. Create a new Nintex Workflow content database using Central Admin Nintex Administration -> Database Management – > Add New   !!! make sure to use the SharePoint application farm account.
  2. Execute IISreset
  3. Stop IIS web application that contains the site collection.
  4. Stop SharePoint timer service on the entire farm.
  5. Run nwadmin -o movedata  with Farm Account  to move data to the new NW-CDB.
  6. Map the new SharePoint Content database  to the new NW-CDB using Central Admin Nintex Administration – > Database Management -> mapping
  7. Restart the web application.

UAT :

Confirm display of visual and detailed workflow history for a workflow that is either “In progress” or “Completed.”

Start a new instance of an existing workflow and confirm that it starts, that it enters an “In progress” status, and that visual and detailed workflow history are displayed.

!!!  stopping the IIS on the web part will prevent corrupted NW_CDB

NWAdmin.exe -o MoveData [-Url <siteCollectionUrl>] [-SourceDatabase <connection string>] [-TargetDatabase <connection string>] [-RetainSourceData]
Name Description
-Url The url to the top level site of the site collection that data will be moved for.
-SourceDatabase A database connection string to the Nintex Workflow database to extract data from. Use when retrieving data from an external database not connected to the target environment.
-TargetDatabase A database connection string to the Nintex Workflow database to move data from. If a value is not provided the console UI will prompt for the target database.

Example executing the command and output  ! execution is slow wait for it to end:

C:\Users\SP_FarmAccountQAS> NWAdmin.exe -o MoveData -Url http://yourdomain/yoursitecollection

Before continuing this operation, please stop the following on each server:
        SharePoint IIS web site
        SharePoint 2010 Timer Service
If these services are not stopped, workflows may continue adding data, leaving t
he instance in an invalid state.

It is recommended that the source and target content databases are backed up before continuing.

Data will be moved for site collection http://yourdomain/yoursite (ID: cfb48ab0-b2d3-4aba-a891-xxxxxxxxxxx).

Enter the ID of the content database to move workflow data for this site collect
ion to (or any other value to abort):

ID 0:   Provide connection string
ID 2:   DataSource: servername          Database: sourcedatabasename

ID 3:   DataSource: servername          Database: target datasourcename

Target database id:
3
Restart each service to continue workflow operation.
PS C:\Users\\SP_FarmAccountQAS>  NWAdmin.exe -o MoveData -Url http://yourdomain/yoursite

 

Ref :
Split Databases

NWAdmin Guide.