I find two solutions with SQL and esProc on cross database computing, like belows, hope for a Java solution.

With SQL:
SELECT salesMan
FROM (SELECT salesMan,
row_number() OVER (ORDER BY isrCount DESC) descOrder,
row_number() OVER (ORDER BY isrCount ASC) ascOrder
FROM (SELECT salesMan,
COUNT(*) isrCount
FROM insurance where salesDate>= ? and salesDate<=?
GROUP BY salesMan
)
)
WHERE descOrder=1 OR ascOrder=1 ORDER BY descOrder

With esProc solution,

A B
1 $select*from insurance where salesDate>=? And salesDate<=?
2=insurance.group(salesMan)
3=A2.sort(~.len())
4=A3.m([-1,1])
5=A4.(salesMan)

Can anyone give me a solution with Java code?