Your suffering comes from the "where ba.bankaccountID = u.bankaccountID"
in the subselect. It means postgres has to run the subselect once for each
row in Users. You want the subselect to run only once, and return one (or
more?) bankaccountid's, then fetch the users from Users.
Just remove the "where ba.bankaccountID = u.bankaccountID" !
> select userID, fname, lname, email, phone, dateEntered, dateCanceled,
> dateSuspended, billAmount, billDate, dateBilled, datePaid, '?' as
> searches
> from Users u
> where bankaccountid in (select bankaccountid
> from bankaccount ba
> where ba.bankaccountID = u.bankaccountID
> and ba.accountnumber = '12345678'
> and ba.routingNumber = '12345678')
> order by UserID desc
> limit 500
New version :
select userID, fname, lname, email, phone, dateEntered, dateCanceled,
dateSuspended, billAmount, billDate, dateBilled, datePaid, '?' as
searches
from Users u
where bankaccountid in (select bankaccountid
from bankaccount ba
WHERE ba.accountnumber = '12345678'
and ba.routingNumber = '12345678')
You could also do this :
select u.* from Users u, bankaccount ba
where u.bankaccountid = ba.bankaccountid
and ba.accountnumber = '12345678'
and ba.routingNumber = '12345678')