The following examples illustrate readpast locking.
To skip all rows that have exclusive locks on them:
select * from titles readpast
To update only rows that are not locked by another session:
update titles set price = price * 1.1 from titles readpast
To use readpast locking on the titles table, but not on the authors or titleauthor table:
select * from titles readpast, authors, titleauthor where titles.title_id = titleauthor.title_id and authors.au_id = titleauthor.au_id
To delete only rows that are not locked in the stores table, but to allow the scan to block on the authors table:
delete stores from stores readpast, authors where stores.city = authors.city
