I am getting below error while configuring Query Database Smart Service:-

You are getting this erro because of the parameters of LIMIT which are ac!'s in this case. As far as I know mysql-connector-java-5.x is more strict in following the documentation of MySQL which states that the LIMIT function only accepts one or two numeric constants. In the case of this model the query is:

SELECT `processid` FROM `absencedetails` where `mainprocessid`=ac!employeeID LIMIT ac!start , ac!Batch


which when subject to validation/execution translates into:

SELECT `processid` FROM `absencedetails` where `mainprocessid`=ac!employeeID LIMIT "" , ""

this is invalid as the parameters for "LIMIT" are empty strings, not a number, thus the error: ".... for the right syntax to use near ''', "" at line x".

If this is what is happening for you then it's because the driver is telling Appian the ac! has to be "Number (Integer)" but when it builds the prepared statement it expects "Text" so it ignores the "Number (Integer)" we are passing and passes an empty string. Assuming this is the issue you are seeing you can consider redesign to use something different for example BETWEEN to limit the amount of data based on a column or try an older driver such as mysql-connector-java-3.x-bin.jar

Thanks Eduardo.
Between clause is working for me. As you mentioned in other posts to use mysql-connector-java-3.x-bin.jar but Appian 7.5 support v5.1.14 or higher version only.

You can also try Patty's suggestion forum.appian.com/.../e-87122