Sybase Slow Update Query

This is a simple update query, but it takes 4 seconds to execute. The statement is:

UPDATE <TABLENAME> SET <FIELD1> = <FIELD1> + <SOMEVALUE1> WHERE <FIELD2> = <SOMEVALUE2>

Other tables in my database executes much faster.
The &#34;problem table&#34; has 100 columns and has 5000 records.

Can anyone help me in this one...

I already found a solution.

I added an index for <FIELD2>, and query runs faster.

Thanks anyway.;)