Resolving The Problem

Option 1: 

Step 1: Stop and restart the db2 instance

Run the following command

oc rsh wdb-db2-0
su - db2inst1

db2 force application all
db2stop

db2start
db2 activate db ilgdb
db2 activate db bgdb
db2 activate db lineage
db2 activate db wfdb

exit
exit

https://www.ibm.com/support/pages/how-resolve-sql1042c%C2%A0%C2%A0unexpected%C2%A0system%C2%A0error%C2%A0occurred%C2%A0upon-database-connection-after-unexpected-outage

Option 3: Rebuilding the wdp-db2-0 and database gets initialized, manual re-sync is required.

In this option, existing persistent storage will be deleted and recreated to fix the corrupted storage volume.

Scale down the wdp-db2-0 pod:

oc scale sts wdp-db2  --replicas=0

Delete the persistent storage volume

# delete pv
export PV=$(oc get pvc  --no-headers $(oc describe pods wdp-db2-0 | grep ClaimName | awk '{ print $2 }' ) | awk '{ print $3 }')
oc delete pv $PV

# delete pvc
export PVC=$(oc describe pods wdp-db2-0 | grep ClaimName | awk '{ print $2 }' )
oc delete pvc $PVC

Scale back the wdp-db2-0 to 1

oc scale sts wdp-db2  --replicas=1

This will rebuild the wdp-db2-0 datatabase instance. You can check the status  in pods log

oc logs wdp-db2-0 -f

Wait for the pods to come up. After that you need to resync the glossary terms, workflow

delete the following service pods:

wkc-glossary-service, wkc-workflow-service, wdp-policy-service, wdp-lineage

oc delete pods $(oc get pods --no-headers | egrep 'wkc-glossary-service|wdp-policy-service|wdp-lineage|wkc-workflow-service'|grep -iv "Completed")

Check the status of the rebuilt database and tables

oc rsh wdp-db2-0

su - db2inst1

db2 connect to ilgdb

db2 "select tabname from syscat.tables where tabschema = 'DB2INST1'"

 Now you can notice the database is rebuilt.