Insomnia can be caused by psychiatric conditions such as depression. Psychological struggles can make it hard to sleep, insomnia itself can bring on changes in mood, and shifts in hormones and physiology can lead to both psychiatric issues and insomnia at the same time.
Lock modes specify different kinds of locks. The choice of which lock mode to apply depends on the resource that needs to be locked. The following three lock types are used for row-and page-level locking: 1  Shared (S). 2  Exclusive (X).3  Update (U).nce an exclusive lock is set for the page (or row), no other lock can be placed on the same resource. NOTE. The database system automatically chooses the appropriate lock mode according to the operation type (read or write). An update lock can be placed only if no other update or exclusive lock exists.
A row share lock (RS) , also called a subshare table lock (SS) , indicates that the transaction holding the lock on the table has locked rows in the table and intends to update them. An SS lock is the least restrictive mode of table lock, offering the highest degree of concurrency for a table.ow Locks (TX) A row lock, also called a TX lock, is a lock on a single row of a table. A transaction acquires a row lock for each row modified by one of the following statements: INSERT, UPDATE, DELETE, MERGE, and SELECT ... FOR UPDATE. The row lock exists until the transaction commits or rolls back.