DS Fault Message: Error in 'createProcessedPreparedStatement' in WSO2 DataService - mysql

Question

I have created a Dataservice in WSO2 to execute SQL Query TRUNCATE TABLE Student and expose it as an API , but i got this error
[2022-12-07 16:33:57,222] ERROR {DBInOnlyMessageReceiver} - Error in
in-only message receiver DS Fault Message: Error in DS non result
invoke. DS Code: DATABASE_ERROR Nested Exception:-
javax.xml.stream.XMLStreamException: DS Fault Message: Error in
'SQLQuery.processStoredProcQuery': DS Fault Message: Error in
'createProcessedPreparedStatement' DS Code: UNKNOWN_ERROR Nested
Exception:- java.sql.SQLException: Unable to retrieve metadata for
procedure.
DS Code: DATABASE_ERROR Source Data Service:- Name: RADMINDataService
Location:
/home/master/Downloads/IntegrationStudio/runtime/microesb/tmp/carbonapps/-1234/1670427210936TestCompositeApplication_1.0.0.car/RADMINDataService_1.0.0/RADMINDataService-1.0.0.dbs
Description: Exposing the radmin data service as a REST service
Default Namespace: http://ws.wso2.org/dataservice/samples/json_sample
Current Request Name: _gettruncatenumseq Current Params: {} Nested
Exception:- DS Fault Message: Error in
'createProcessedPreparedStatement' DS Code: UNKNOWN_ERROR Nested
Exception:- java.sql.SQLException: Unable to retrieve metadata for
procedure.
at
org.wso2.micro.integrator.dataservices.core.dispatch.SingleDataServiceRequest.processSingleRequest(SingleDataServiceRequest.java:117)
at
org.wso2.micro.integrator.dataservices.core.dispatch.SingleDataServiceRequest.processRequest(SingleDataServiceRequest.java:66)
at
org.wso2.micro.integrator.dataservices.core.dispatch.DataServiceRequest.dispatch(DataServiceRequest.java:358)
at
org.wso2.micro.integrator.dataservices.core.DataServiceProcessor.dispatch(DataServiceProcessor.java:40)
at
org.wso2.micro.integrator.dataservices.core.DBInOnlyMessageReceiver.invokeBusinessLogic(DBInOnlyMessageReceiver.java:52)
at
org.apache.axis2.receivers.AbstractMessageReceiver.receive(AbstractMessageReceiver.java:110)
at org.apache.axis2.engine.AxisEngine.receive(AxisEngine.java:180)
at
org.apache.synapse.transport.passthru.ServerWorker.processNonEntityEnclosingRESTHandler(ServerWorker.java:376)
at
org.apache.synapse.transport.passthru.ServerWorker.run(ServerWorker.java:190)
at
org.apache.axis2.transport.base.threads.NativeWorkerPool$1.run(NativeWorkerPool.java:172)
at
java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1128)
at
java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:628)
at java.base/java.lang.Thread.run(Thread.java:834) Caused by:
javax.xml.stream.XMLStreamException: DS Fault Message: Error in
'SQLQuery.processStoredProcQuery': DS Fault Message: Error in
'createProcessedPreparedStatement' DS Code: UNKNOWN_ERROR Nested
Exception:- java.sql.SQLException: Unable to retrieve metadata for
procedure.
This is my configuration file
<query id="truncatenum" useConfig="mysql">
<sql><![CDATA[TRUNCATE TABLE Student]]></sql>
</query>
<resource method="GET" path="truncatenum">
<description />
<call-query href="truncatenum"/>
</resource>

Answer 1

I don't think the error is caused by the code snippet you shared. The following seems correct.
<query id="truncatenum" useConfig="mysql">
<sql><![CDATA[TRUNCATE TABLE Student]]></sql>
</query>
<resource method="GET" path="truncatenum">
<description />
<call-query href="truncatenum"/>
</resource>
Probably one of the queries you have doesn't match the input parameters you are providing. Hence double check all the other queries you have.
Update
You are correct the TRUNCATE query is executed as a STOREDPROC. I had a closer look at the source-code and it seems if the QUERY String doesn't start with one of the following it's inferred as a STOREDPROC. This is definitely a bug in WSO2.
The weird thing is, in my case the TRUNCATE query is executed as a Stored Procedure successfully. So I assume there is a difference in your Dataeervice from the one I'm trying. Can you create the following Dataservice as it is and try it out? (Just change the connection parameters)
Dataservice
<data name="RESTDataService" serviceNamespace="http://ws.wso2.org/dataservice/samples/json_sample" transports="http https">
<description>Exposing the data service as a REST service.</description>
<config id="default">
<property name="driverClassName">com.mysql.jdbc.Driver</property>
<property name="url">jdbc:mysql://localhost:3306/school_db</property>
<property name="org.wso2.ws.dataservice.user">root</property>
<property name="org.wso2.ws.dataservice.password">root123456</property>
</config>
<resource method="GET" path="truncatenum">
<description />
<call-query href="truncatenum" />
</resource>
<query id="truncatenum" useConfig="default">
<sql><![CDATA[TRUNCATE TABLE students]]></sql>
</query>
</data>
Request
curl --location --request GET 'http://localhost:8290/services/RESTDataService/truncatenum'
If you still get the error. Please enable DEBUG logs for the package org.wso2.micro.integrator.dataservices and share the logs.