How many types of locks are there in DB2?

How many types of locks are there in DB2?

DB2 supports locking at four levels, or granularities: table space-, table-, page-, and row-level locking. DB2 also provides LOB locking for large objects (BLOBs, CLOBs, and DBCLOBs). Locks can be taken at any level in the locking hierarchy without taking a lock at the lower level.

What are the different modes of lock?

At the table level, there are five different types of locks:

• Exclusive (X)
• Shared (S)
• Intent exclusive (IX)
• Intent shared (IS)
• Shared with intent exclusive (SIX)

How the locks can be classified in DB2?

Locks can be classified based on size, duration and mode.

What are the two types of lock?

Types of Locks

• Cylindrical Locksets—Often called key-in-knob or key-in-lever locks.
• Dead-Bolt Locks—Sometimes called tubular dead bolts.
• Mortise Locks—Mortised or recessed into the edge of the door.
• Drop-Bolt Locks (often called jimmy-proof locks)—Auxiliary locks similar to dead bolts.

What is S lock in Db2?

S lock (share) The lock owner and any concurrent processes can read, but not change, data in the table, partition, or table space. The lock owner does not need page or row locks on data it reads.

What are page locks in Db2?

With page locks, the second application to access the page must wait for the first to finish and might time out. With row locks, the two applications can access the same page simultaneously. However, they might encounter a deadlock while trying to access the same set of rows.

What is a six lock?

SIX. Shared intent exclusive locks. SIX (“shared with intent to update”) locks can be considered as combination of S (shared) locks and IX (intent exclusive) locks. SIX locks are used in table locking strategies to minimize the extent of exclusive locking requirements.

What is bind in DB2?

STEP 4 – DB2 BIND The bind process reads the DBRM that was created in the precompile and prepares an access path to the data. This access path, along with the consistency token, is stored in the DB2 catalog as a Package. Every Package is bound into a Package List, or Collection.

Are all locks in the world different?

While there is seemingly scope for every door lock in the world to require a unique key, reality is that a limited number of different key and door lock combinations exist. This is simply because key and door lock manufacturers don’t need to go through the hassle of making each door lock unique.

What are locked attributes?

The only type of object that you can lock explicitly is a table. The database manager also sets locks on other types of resources, such as rows and table spaces.