Database details can be changed via TCT - https://docs.tibco.com/pub/amx-bpm/4.3.0/doc/html/install/GUID-DA7622CD-2CBA-4190-BB83-457CB1F59157.html

The scope of this article is how to change BPM database details via TIBCO ActiveMatrix (AMX) Administrator. 

This article lists the steps needed to change BPM database details using TIBCO ActiveMatrix Administrator

ALL

1. Stop the system AMX BPM application, commonly known as amx.bpm.app. 

2. Go to Shared Objects → Resource Templates → On the left pane - select type as "JDBC" from the drop-down → Select the BPM Environment → Select Application "amx.bpm.app". 

In the main pane, the following resource templates should be listed:

DataSource
DataSourceBDS
DataSourceDirect

3. Make the changes by selecting each of these templates - 

select DataSource: database user credentials are in the General tab. 

for connection details - (bottom panel) click on Advanced → Connection Properties → make changes → Save → in the pop-up "UNCHECK" the option of restarting all affected applications → Save → Ensure all the resource instances are “Running” with “In Sync” status in the Resource Instances tab.

select DataSourceBDS: database user credentials are in the General tab. 

for connection details - (bottom panel) click on Advanced → Connection Properties → make changes → Save → in the pop-up "UNCHECK" the option of restarting all affected applications → Save → Ensure all the resource instances are “Running” with “In Sync” status in the Resource Instances tab.

select DataSourceDirect: both database user credentials and connection details are in the General tab. 

make changes → Save → in the pop-up "UNCHECK" the option of restarting all affected applications → Save → Ensure all the resource instances are “Running” with “In Sync” status in the Resource Instances tab.

3. Start amx.bpm.app, which was stopped in step #1

4. Restart all hosts which manage BPM nodes with -clearCache option:

<CONFIG_HOME>/tibcohost/<BPM host>/host/bin/tibcohost stop
./tibcohost start -clearCache &

https://docs.tibco.com/pub/amx-bpm/4.3.0/doc/html/install/GUID-DA7622CD-2CBA-4190-BB83-457CB1F59157.html