​My clients are converting from C10 to C11. And along with that change we are changing the Framework manager packages and Data Source from using CQM (compatible query mode), which for us used either OleDB or SQL Native Client, to DQM (dynamic query mode), which uses the java jdbc driver. We have come across many reports that worked in CQM that throw an error in DQM. This is an informal list of what we have experienced along with some notes from a MotioPI presentation..

Errors in DQM that were not errors in CQM or differences in report output from DQM to CQM

1) some variation of error "StringColumnVector incompatible with com.cognos.xqe.runtree.relational.vectorization.DecimalColumnVector" means that a data type is being compared to a different type. In this case a string was being compared to a decimal.

2) Comments in advanced filter, sql query, custom calculation can cause sporadic errors.  Remove all comments,  '--' or '/* */'.

3) All SUM() functions need to be replaced with Total()

4) some calculations will default to 2.00 whereas CQM might have defaulted to 2

5) Some functions provide a different result, such as total(total(sales))
6) Filter on calculated/aggregate column may lead to different results. CQM always uses AFTER aggregations regardless if you select before or after. DQM honors the aggregation choice which may result in a difference
7) DQM may apply a different order of operations that causes changes in report output. Report level cardinality definition lead to change in report output. DQM is more rigid on cardinality
8) DQM will show first message, even if only a warning. Will not show the next message which might be an error. Need to clear up all warnings to see errors. CQM shows the first error.
9) DQM gives sporadic errors with joins in the filter. Some of our clients had filters that contained an expression that compared fields from two different queries instead of doing a JOIN.  CQM gave no errors.
10) DQM errors "Your request could not be completed because the Query Service is busy" caused by Initial JVM heap size and JVM heap size limit in the Query Service not having enough memory.

Feel free to add to the list or to make any comments.

------------------------------
brenda grossnickle
------------------------------
#CognosAnalyticswithWatson

Hello Brenda,

We're also in a CQM to DQM migration, a lot of errors are recognizable. In addition to your list.

What's not general known or documented is that when you use a multilingual framework in CQM it's not completely working in DQM. Referenced query items will be not translated. So in general translations only work in reports with just one query.

According IBM is this a "known missing feature". Because this is an essential feature for a lot of customers I've added an idea to the idea portal. Your vote would be greatly appreciated.

https://ibm-data-and-ai.ideas.aha.io/ideas/CAOP-I-2437

------------------------------
--
------------------------------

Thank you so much @brenda grossnickle ! This helps tremendously. I have come across some of these but your explanations also help a lot.

Just fyi, our team decided to not convert FM projects to DQM at the same time as upgrading to C11. Instead we are converting packages on an as needed basis, when having to use features that work only with DQM packages. This gave us a bit of a breathing room, not having to do everything all at once. We could do this as we are a small, in house team, only having our own reports to deal with.

------------------------------
Adrienne Beronilla
Senior Financial Systems Analyst
Franklin Templeton
------------------------------

DQM is for better report performance( memory caching and JDBC connection) and utilizing the server processing capacity ( both server and Cognos server 64-bit architecture) in a better way.

I remember We could not use the XML data source when we migrated from CQM to DQM. We had an issue with formating and calculated data items.
I feel, build any new things in the DQM model and slowly convert the model and reports from CQM to DQM by business or subject area.

------------------------------
Ramanujam Rajagopal
------------------------------

Original Message:
Sent: Mon December 09, 2019 11:25 AM
From: Adrienne Beronilla
Subject: Report differences and errors from CQM to DQM

Thank you so much @brenda grossnickle ! This helps tremendously. I have come across some of these but your explanations also help a lot.

Just fyi, our team decided to not convert FM projects to DQM at the same time as upgrading to C11. Instead we are converting packages on an as needed basis, when having to use features that work only with DQM packages. This gave us a bit of a breathing room, not having to do everything all at once. We could do this as we are a small, in house team, only having our own reports to deal with.

------------------------------
Adrienne Beronilla
Senior Financial Systems Analyst
Franklin Templeton
------------------------------

@Ramanujam Rajagopal ​ We have not seen any performance improvements from CQM to DQM. In fact we are having across the board system resource issues. When migrating from C10 to C11 we also migrated from CQM to DQM, All new servers with more cores, memory, and newer Windows Server versions were stood up. Of course as vendors/resellers we always hear the complaints instead of the complements and of course nobody likes change. But there has been a ton of complaints and not one complement from the migration. And an additional migration issue that is not Cognos related has been the upgrade from SQL 2008/2012 to SQL 2016, which has a new Cardinality Estimator and occasionally makes an historically fast report run like a dog.

------------------------------
brenda grossnickle
BI Programmer Analyst
FIS
------------------------------

Original Message:
Sent: Tue December 10, 2019 09:02 AM
From: Ramanujam Rajagopal
Subject: Report differences and errors from CQM to DQM

DQM is for better report performance( memory caching and JDBC connection) and utilizing the server processing capacity ( both server and Cognos server 64-bit architecture) in a better way.

I remember We could not use the XML data source when we migrated from CQM to DQM. We had an issue with formating and calculated data items.
I feel, build any new things in the DQM model and slowly convert the model and reports from CQM to DQM by business or subject area.

------------------------------
Ramanujam Rajagopal
------------------------------


Original Message:
Sent: Mon December 09, 2019 11:25 AM
From: Adrienne Beronilla
Subject: Report differences and errors from CQM to DQM

Thank you so much @brenda grossnickle ! This helps tremendously. I have come across some of these but your explanations also help a lot.

Just fyi, our team decided to not convert FM projects to DQM at the same time as upgrading to C11. Instead we are converting packages on an as needed basis, when having to use features that work only with DQM packages. This gave us a bit of a breathing room, not having to do everything all at once. We could do this as we are a small, in house team, only having our own reports to deal with.

------------------------------
Adrienne Beronilla
Senior Financial Systems Analyst
Franklin Templeton

@Brenda,
Sorry to hear about it. It looks like something blocks the data flow either by network or firewall. Please take a few slow running SQL from the Cognos and run it in toad or SQL developer. Please check the properties of the metrics in the report If the report does not run quick. I still remember I had to change the properties of the data item and the processing method for the report level like run it against database only or local processing.
If you have a Distributed Environment, Please make one server to 32-bit Architecture, and another one is 64 Bit.
Using the rerouting the method and test the same report.
Clear the browser cache and query service cache ( for DQM) when testing.

Please check before running the report.
I am not sure about windows server But check the Windows server page file setup ( In Linux, we make sure installed the IBM recommended packages and system configuration)
Ask DBA to monitor the simple report.
Monitor the Cognos content store- If the size is big, please remove all unwanted files from the content store.

------------------------------
Ramanujam Rajagopal
------------------------------

Original Message:
Sent: Tue December 10, 2019 09:31 AM
From: brenda grossnickle
Subject: Report differences and errors from CQM to DQM

@Ramanujam Rajagopal ​ We have not seen any performance improvements from CQM to DQM. In fact we are having across the board system resource issues. When migrating from C10 to C11 we also migrated from CQM to DQM, All new servers with more cores, memory, and newer Windows Server versions were stood up. Of course as vendors/resellers we always hear the complaints instead of the complements and of course nobody likes change. But there has been a ton of complaints and not one complement from the migration. And an additional migration issue that is not Cognos related has been the upgrade from SQL 2008/2012 to SQL 2016, which has a new Cardinality Estimator and occasionally makes an historically fast report run like a dog.

------------------------------
brenda grossnickle
BI Programmer Analyst
FIS
------------------------------


Original Message:
Sent: Tue December 10, 2019 09:02 AM
From: Ramanujam Rajagopal
Subject: Report differences and errors from CQM to DQM

DQM is for better report performance( memory caching and JDBC connection) and utilizing the server processing capacity ( both server and Cognos server 64-bit architecture) in a better way.

I remember We could not use the XML data source when we migrated from CQM to DQM. We had an issue with formating and calculated data items.
I feel, build any new things in the DQM model and slowly convert the model and reports from CQM to DQM by business or subject area.

------------------------------
Ramanujam Rajagopal


Original Message:
Sent: Mon December 09, 2019 11:25 AM
From: Adrienne Beronilla
Subject: Report differences and errors from CQM to DQM

Thank you so much @brenda grossnickle ! This helps tremendously. I have come across some of these but your explanations also help a lot.

Just fyi, our team decided to not convert FM projects to DQM at the same time as upgrading to C11. Instead we are converting packages on an as needed basis, when having to use features that work only with DQM packages. This gave us a bit of a breathing room, not having to do everything all at once. We could do this as we are a small, in house team, only having our own reports to deal with.

------------------------------
Adrienne Beronilla
Senior Financial Systems Analyst
Franklin Templeton

​@Ramanujam Rajagopal​, how do you clear the query service cache?

------------------------------
brenda grossnickle
BI Programmer Analyst
FIS
------------------------------

Original Message:
Sent: Tue December 10, 2019 11:54 AM
From: Ramanujam Rajagopal
Subject: Report differences and errors from CQM to DQM

@Brenda,
Sorry to hear about it. It looks like something blocks the data flow either by network or firewall. Please take a few slow running SQL from the Cognos and run it in toad or SQL developer. Please check the properties of the metrics in the report If the report does not run quick. I still remember I had to change the properties of the data item and the processing method for the report level like run it against database only or local processing.
If you have a Distributed Environment, Please make one server to 32-bit Architecture, and another one is 64 Bit.
Using the rerouting the method and test the same report.
Clear the browser cache and query service cache ( for DQM) when testing.

Please check before running the report.
I am not sure about windows server But check the Windows server page file setup ( In Linux, we make sure installed the IBM recommended packages and system configuration)
Ask DBA to monitor the simple report.
Monitor the Cognos content store- If the size is big, please remove all unwanted files from the content store.

------------------------------
Ramanujam Rajagopal
------------------------------


Original Message:
Sent: Tue December 10, 2019 09:31 AM
From: brenda grossnickle
Subject: Report differences and errors from CQM to DQM

@Ramanujam Rajagopal ​ We have not seen any performance improvements from CQM to DQM. In fact we are having across the board system resource issues. When migrating from C10 to C11 we also migrated from CQM to DQM, All new servers with more cores, memory, and newer Windows Server versions were stood up. Of course as vendors/resellers we always hear the complaints instead of the complements and of course nobody likes change. But there has been a ton of complaints and not one complement from the migration. And an additional migration issue that is not Cognos related has been the upgrade from SQL 2008/2012 to SQL 2016, which has a new Cardinality Estimator and occasionally makes an historically fast report run like a dog.

------------------------------
brenda grossnickle
BI Programmer Analyst
FIS


Original Message:
Sent: Tue December 10, 2019 09:02 AM
From: Ramanujam Rajagopal
Subject: Report differences and errors from CQM to DQM

DQM is for better report performance( memory caching and JDBC connection) and utilizing the server processing capacity ( both server and Cognos server 64-bit architecture) in a better way.

I remember We could not use the XML data source when we migrated from CQM to DQM. We had an issue with formating and calculated data items.
I feel, build any new things in the DQM model and slowly convert the model and reports from CQM to DQM by business or subject area.

------------------------------
Ramanujam Rajagopal


Original Message:
Sent: Mon December 09, 2019 11:25 AM
From: Adrienne Beronilla
Subject: Report differences and errors from CQM to DQM

Thank you so much @brenda grossnickle ! This helps tremendously. I have come across some of these but your explanations also help a lot.

Just fyi, our team decided to not convert FM projects to DQM at the same time as upgrading to C11. Instead we are converting packages on an as needed basis, when having to use features that work only with DQM packages. This gave us a bit of a breathing room, not having to do everything all at once. We could do this as we are a small, in house team, only having our own reports to deal with.

------------------------------
Adrienne Beronilla
Senior Financial Systems Analyst
Franklin Templeton

------Original Message------

​@Ramanujam Rajagopal​, how do you clear the query service cache?

------------------------------
brenda grossnickle
BI Programmer Analyst
FIS
------------------------------

#CognosAnalyticswithWatson