How to compare database query results with a string using Bean Shell Assertion in JMeter - jmeter-5.0

Question

I am new to JMeter.
In my Test Plan I am using
JDBC Connection Configuration to connect SQL database.
JDBC Request to run the select query. And I used Variable Names field to store the FK_SiteId from the database response as shows below.
I used Debug Sampler to print the FK_SiteId in the results. Please find the Debug result.
I am using BeanShell Assertion to compare the Actual FK_SiteId with Expected FK_SiteId as shown below.
Please find the error message below.
2019-03-04 12:25:45,549 INFO o.a.j.e.StandardJMeterEngine: Running the test! 2019-03-04 12:25:45,549 INFO o.a.j.s.SampleEvent: List of sample_variables: [] 2019-03-04 12:25:45,549 INFO o.a.j.g.u.JMeterMenuBar: setRunning(true, *local*)
2019-03-04 12:25:45,661 INFO o.a.j.e.StandardJMeterEngine: Starting ThreadGroup: 1 : SQL Database Connection 2019-03-04 12:25:45,661 INFO o.a.j.e.StandardJMeterEngine: Starting 1 threads for group SQL Database Connection.
2019-03-04 12:25:45,661 INFO o.a.j.e.StandardJMeterEngine: Thread will continue on error
2019-03-04 12:25:45,661 INFO o.a.j.t.ThreadGroup: Starting thread group... number=1 threads=1 ramp-up=1 perThread=1000.0 delayedStart=false
2019-03-04 12:25:45,677 INFO o.a.j.t.ThreadGroup: Started thread group number 1
2019-03-04 12:25:45,677 INFO o.a.j.e.StandardJMeterEngine: All thread groups have been started
2019-03-04 12:25:45,677 INFO o.a.j.t.JMeterThread: Thread started: SQL Database Connection 1-1
2019-03-04 12:25:50,564 ERROR o.a.j.u.BeanShellInterpreter: Error invoking bsh method: eval Sourced file: inline evaluation of: ``String ActialResult = vars.get(${FK_SiteId}); String ExpectedResult = "14001"; . . . '' : Typed variable declaration : Attempt to access property on undefined variable or class name
2019-03-04 12:25:50,564 WARN o.a.j.a.BeanShellAssertion: org.apache.jorphan.util.JMeterException: Error invoking bsh method: eval Sourced file: inline evaluation of: ``String ActialResult = vars.get(${FK_SiteId}); String ExpectedResult = "14001"; . . . '' : Typed variable declaration : Attempt to access property on undefined variable or class name
2019-03-04 12:25:50,564 ERROR o.a.j.u.BeanShellInterpreter: Error invoking bsh method: eval Sourced file: inline evaluation of: ``String ActialResult = vars.get(${FK_SiteId}); String ExpectedResult = "14001"; . . . '' : Typed variable declaration : Attempt to access property on undefined variable or class name
2019-03-04 12:25:50,564 WARN o.a.j.a.BeanShellAssertion: org.apache.jorphan.util.JMeterException: Error invoking bsh method: eval Sourced file: inline evaluation of: ``String ActialResult = vars.get(${FK_SiteId}); String ExpectedResult
= "14001"; . . . '' : Typed variable declaration : Attempt to access property on undefined variable or class name
2019-03-04 12:25:50,564 INFO o.a.j.t.JMeterThread: Thread is done: SQL Database Connection 1-1
2019-03-04 12:25:50,564 INFO o.a.j.t.JMeterThread: Thread finished: SQL Database Connection 1-1
2019-03-04 12:25:50,564 INFO o.a.j.e.StandardJMeterEngine: Notifying test listeners of end of test
2019-03-04 12:25:50,564 INFO o.a.j.g.u.JMeterMenuBar: setRunning(false, *local*)
Can anyone tell me where I am going wrong

Answer 1

Your variable was saved as FK_SiteId_1. You can access this variable by
vars.get("FK_SiteId_1") or directly ${FK_SiteId_1}
Use log.info(... to check the variable value
I prefer to use vars.get solution.