Sunday, April 7, 2013

Locks in Oracle - Part 1

Apart from parsing
  1. What happens when i issue an update statement ?
  2. How does Oracle comply with the properties of a Database Transaction aka ACID properties
If interested read further :)

A transaction is nothing but SQL statements which is tracked with an unique transaction ID until commit / rollback / DDL are issued. ooh ooh hold on, before i get into the internals lets have a quick view on the basic's of Locks.

Is this true - "Picture Speaks Louder Than Words"

For the next series of diagrams concentrate on the below arrow in each diagram- 










Lets start with a basic query and check what happens
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does these diagrams helped you to understand something, will continue internals soon 

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