What is Agent Load Balancing in ODI ? What is Commit and Isolation levels in ODI Procedures ?

Answer:- 



Standalone agent Load Balancing:- 



Load Balancing is a feature to provide optimal performance by distributing the execution of session over several agents. When an agent has linked agents defined, it automatically distributes the execution of its incoming sessions over the agents. Session distribution is made proportionally to the value specified in the Maximum Number of Sessions supported by an agent. This value reflects the agent’s availability and processing capabilities and is relative to the other agents. If Agent A has a value twice that of Agent B, A will receive twice the number of sessions B receives.



Note that the parent agent still takes charge of the creation of the session in the repository. Load balancing separates the creation and execution of a session. If you want the parent agent to take charge of some of the sessions and not just distribute the sessions, then it must be linked to itself.



When using load balancing, it is possible that an agent could reach the maximum number of sessions allowed. In this situation, the incoming sessions for this agent will be put in a Queued status. The Use pre-emptive load balancing Agent property allows for redistribution of queued sessions to agents as sessions finish. Otherwise, sessions are not redistributed.

Each ODI agent supports multiple sessions. Several sessions running within one agent run within the same agent process, each session using a different thread in this process. With load balancing, as sessions run in different agents, they run in different processes. On multi-processor machines, this can provide dramatic increase of performance, without having to define it at run-time. Load balancing is automatically handled provided that agents are correctly linked.

Commit and Isolation levels in Procedures:



Commit levels:-



Procedure is made up of group of tasks which are executed step by step .Each task is an SQL statement which needs to be committed. To manage the commit levels we have options like Auto commit and Transaction 0 to Transaction 9. Auto commit simply commits particular task in procedure. Transactions 0 to 9 are used to group the tasks need to commit at a time sequentially. This way we can manage the commit levels in ODI.



Isolation Levels:-

You will find this setting in ODI procedure you can set Transaction Isolation level for Source code as well as for Target code.

These levels are classified into four Committed, Uncommitted (Dirty), Repeatable, Serialazable.

Committed: The Tasks in the procedure will read the only committed data from the source.



Uncommitted (Dirty): The Tasks in the Procedure will read uncommitted data from the source (oracle doesn't support)



Repeatable: The Tasks in the Procedure while reading the huge amount of data it will lock the rows not to update at the point of time to avoid inconsistency.



Serialazable: The Tasks in the Procedure while reading the huge amount of data it will lock the respective table not to update at the point of time to avoid inconsistency.




How to perform Encrypting and Decrypting on ODI Procedures :- 



Encrypting a Knowledge Module (KM) or a procedure allows you to protect valuable code. An encrypted KM or procedure can neither be read nor modified if it is not decrypted. The commands generated in the log by an Encrypted KM or procedure are also unreadable.



Oracle Data Integrator uses a DES Encryption algorithm based on a personal encryption key. This key can be saved in a file and reused to perform encryption or decryption operations.



WARNING:



There is no way to decrypt an encrypted KM or procedure without the encryption key. It is therefore strongly advised to keep this key in a safe location. It is also advised to use a unique key for all the developments.



To encrypt a KM or a Procedure:



Right-click the KM or procedure you wish to encrypt.



Select Encrypt.



In the Encryption Option dialog, either:



Select the Encrypt with a personal key option and select an existing Encryption Key file



Select the Encrypt with a personal key option and then type in (or paste) the string corresponding to your personal key



or let Oracle Data Integrator generate a key using the Get a new encryption key option.



The Encryption Key dialog appears when the encryption is finished. From this dialog, you can save the key.



Note that if you type in a personal key with too few characters, an invalid key size error appears. In this case, please type in a longer personal key. A personal key of 10 or more characters is required.



To decrypt a KM or a procedure:



Right-click the KM or procedure that you wish to decrypt.



Select Decrypt.



In the KM/Procedure Decryption dialog, either:



Select an existing encryption key file



or type in (or paste) the string corresponding to your personal key.



A message appears when the decryption has finished.