It's easy to convert a SELECT into an UPDATE.

You have 2 options depending on the complexity of the UPDATE. You can keep the FROM and use a table alias in the UPDATE.

UPDATE t SET

ExpiryDate = '20160630'

from mytable t

where AccNumber between 1 and 500;

Or you could remove the FROM clause

UPDATE mytable SET

ExpiryDate = '20160630'

where AccNumber between 1 and 500;

Note that:

- I added a semicolon which is optional but might not be that way in the future (it isn't for certain statements).

- I removed the quotes to handle the values as integers.

- I'm using the ISO format for dates which is not dependent on any settings, unlike most other formats.