Shared (S) and Intent Shared(IS)

"Intent" locks (IX, IS) are put on higher-level in locking hierarchy to indicate that non-intent lock will be requested on lower level. For example, if you update one row, S lock is put on a database, IX lock on table, IX lock on a page, and X lock on a row.IX locks are mutually compatible, e.g. you can have multiple IX locks on the same page, they are not blocking each other. IX means "on the lower level there is X (or soon will be requested X)".