Select * from table where fieldname = 'abc'
Select * from table where fieldname = 'XYï¿½'
- My query 1 executes in 150mS
- My query 2 executes in 5000mS
Both return zero results (
XYï¿½ don't appear in database).
After I run query 2 after which rerun my query 1, query 1 begins taking extended period if it's run in same session (around 2000ms rather than earlier 150ms)
My fieldname is indexed (non-clustered index).
I'm using Adaptive Server Enterprise/12.5.4
I attempted to perform a show arrange for both. Both show same results.
- Why queries with non ascii figures should harder ? Is the fact that something related to indexes?
- Running query 2 shouldn't impact my query 1 response time. Any methods to fix this?
I discovered problem to my problem. TIBCO EMS does some changes to unicode chars(non ascii) which in turn causes query plan in sybase to alter with a non enhanced query plan. When utilizing prepared claims in Java query plan's cached ,consequently all future queries become slow.