Interview Questions.

Question 1. Illustrate On The Architecture Of Dac?

Answer :

DAC incorporates of the DAC customer and the DAC server. It is critical to word they need to realign themselves with Information Integration Service and Information Repository.

Question 2. How To Export And Import Dac Architecture?

Answer :

DAC export and import are generally used for backup or repository metadata. The logical machine and runtime gadgets can facilitate essential and commodity.

Oracle Interview Questions
Question three. Can We Facilitate The Running Of Multiple Plans Related To Accomplishments At The Same Time In Dac?

Answer :

The answer is yes. However, it can be facilitated handiest while the accomplishment process isn't always loading into the identical desk.

Question 4. How Can You Execute The Sql Script With The Help Of Dac? If The Answer Is Yes, Then Illustrate How It Can Be Achieved?

Answer :

The SQL script can be accomplished with the assist of the DAC server. However, it may be applied most effective at the assignment level. It can be executed by means of deciding on the SQL document within the technique of execution.

Oracle DBA Tutorial
Question five. What Do You Mean By An Authentication File?

Answer :

The report of authentication usually authenticates the database wherein the repository lies. On the alternative hand, if you choose growing an authentication record, you then have the freedom to specify the particular desk and password for a exact set of the database.

Oracle DBA Interview Questions
Question 6. What Do You Mean By Table, Task Actions And Index In Dac?

Answer :

The desk refers to override the default conduct for assessing and truncating diverse tables which are being assigned to a particular form of database. On the alternative hand, Task Action refers back to the fact that you can still add a couple of styles of new functionalities related to the conduct of the obligations. It incorporates of failure action, success action, and failure restart. Moreover, index action refers to override the practice of making and dropping indexes.

Question 7. How Can You Differentiate Between Homogeneous And Heterogeneous Plans Related To Accomplishments In Dac?

Answer :

A distinct plan associated with accomplishments refers back to the reality that it is able to extract records from one or more probabilities of supply structures which can be dissimilar. For example, a business organization will have a score of Siebel 7.8 in a single region. On the other hand, an example of Oracle EBS 11 can be in any other role. One also can choose surprising the timing of information extraction while the expert is using this kind of plans associated with accomplishments.  

On the other side, homogenous plans related to accomplishments additionally pulls database systems from various instances of the machine that has originated from the identical source. A appropriate example, in this example, may be in the form of the reality that a enterprise will have Oracle EBS eleven in a single area and time sector and another part of EBS eleven in any other role and time quarter. In the cases mentioned above, facts extraction timing can be altered in order that the business wishes of an company can be met. 

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Question 8. Define How Dac Can Determine The Tasks That Are Needed For A Particular Type Of Subject Area?

Answer :

It is crucial to be aware that a topic location may be defined by means of assigning a reality desk. Moreover, a subject location can also be certain via assigning a hard and fast of truth tables. 

When a subject vicinity is adequately defined, DAC also performs the underneath-mentioned approaches to evaluate the crucial obligations associated with records warehousing.

DAC is concerned with the identification of the source tables for the obligations which can be being diagnosed in techniques previous to the one that changed into called for to carry out 

information warehousing. DAC additionally provides tables to the places of a subject.

With the assist of DAC, one can also do away with an assignment from a selected challenge region with the aid of the use of upload or take away command. These instructions are positioned on the responsibilities tab. 

It is likewise observed within the places of a topic tab. However, when someone deletes a specific undertaking, it receives removed best from the location of a subject until and until you refigure the facts patterns that are positioned within the locations of remember.

It is interesting to notice that the obligations which might be automatically assigned by DAC are targeted to a subject area. It may be completed so by means of selecting the Inactive checkbox. 

It is located within the locations of a subject tab.

Moreover, DAC also plays this system in a recursive manner. It is likewise important to notice that till all vital assignments are completed, they are usually introduced to the tab this is positioned in the difficulty vicinity.

A venture is commonly brought to the vicinity of the difficulty most effective once. DAC additionally expands or lowers the range of features which can be based totally at the specs related to configuration.

This technique or manner can be resource intensive as DAC installs a wide type of data items into the machine before the reminiscence of the server is exhausted.

DAC additionally identifies the desk of dimensions that are worried with the facts and normally adds those statistics tables to the locations of a subject.

It can also correctly find the related statistics tables which include aggregates that are constantly related to the schedules of dimensions. You also can favor to upload them to the concern area of proportion. 

Question 9. Illustrate On The Various Types Of Dac Repository Objects That Are Usually Held In The Containers Related To Source System?

Answer :

There exist a couple of sorts of DAC repository objects that are important so that it will make sure that the records warehousing obligations are being accomplished in a right manner.

The following are the diverse objects related to the DAC Repository:

Tables: They are also acknowledged by physical tables in DAC.
Assignments: They are also popularly called responsibilities and are typically called a unit of labor loading tables.
Indexes: Indexes are also known as the bodily DAC indexes which enables the cost mission of information.
Data shape Tables: Data shape tables play a pivotal function in the proper size of numerous varieties of facts. They are also referred to as the indexes related to DAC.
Group of Tasks: The classification of assignments may be amassed to run as a particular collective institution.
Plans associated with the execution process: A facts alteration technique this is commonly described on the places of a topic. These web sites of an problem are the center places that want to be altered at various frequencies in a particular body of mind.
Time schedules or time-frequency: It is related to the precise evaluation of the jogging of the execution system.
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Question 10. Illustrate The Process Of How Dac Usually Keeps Track Of The Time Of Refresh For The Source Tables And Target Tables?

Answer :

The dates related to refresh are usually tracked for the tables. The tables can be a number one supply or also can be a prime target. These number one and source goal tables are generally primarily based on the finished trial of particular plans related to accomplishments. The DAC may even run the overall load command for the assignments which might be based totally on a desk that is a number one source of a goal. It additionally runs the complete load of powers which are normally assigned to obligations in case the date of refresh in opposition to the desk is null. In case there are a whole lot of multiple assets, the refresh dates might continually cause an incremental load. DAC could run the full load command shape, in truth, the supply tables haven't any refresh dates.

Question eleven. Shed Light On The Merge And Upgrade Options For Dac Version 7.8 And Also For The New Releases?

Answer :

The merge and update choice for DAC version may be completed by the usage of the merge and update process that is gift within the DAC server. The Repository Upgrade is also used for updating DAC. You can use the simplified refresh base from the refresh base menu. It might assist you to update the repository of DAC from an in advance launch of Oracle BI. The applications associated with a new edition may be achieved via comparing and facilitating a file. On the alternative hand, the base of update or substitution is completed while there is a conversion from the older model to a newer one. Quite curiously, the peer to look merge can align diverse DAC times of repositories associated with Data Infrastructure. The base of refresh can also be used for updating the Business Intelligence Applications that are typically gift on the DAC server.

Oracle BI Publisher Interview Questions
Question 12. Define The Execution Related To Micro Etl Plans And Also Illustrate The Process Of Building And Running Them?

Answer :

The performance as compared to Micro ETL plans are also called ETL strategies that may be scheduled on the fixed set of durations. It is crucial to note that these micro plans associated with accomplishments may be categorized into half hourly and hourly foundation. They are associated with the control of subsets or small places of a subject. The DAC server also can music the time of refresh for diverse forms of tables within the plans associated with accomplishments of the micro ETL.

It does so through executing the plans from one-of-a-kind plans associated with execution. It then makes use of the dates of refresh inside the technique bearing on change capture. One can construct and run them with the aid of growing a duplicate of the issue location. You can then choose deactivating the undesirable assignments and might facilitate the creation of latest plans associated with accomplishments for this region of a subject. 

Oracle Interview Questions
Question 13. Explain The Areas Where Execution Pertaining To Micro Etl Plans Have Produced Inaccurate Results On Various Kinds Of Reports?

Answer :

It is vital to notice that the techniques related to Micro ETL can cause issues associated with facts inconsistencies. It also can create a huge trouble of the supply of facts and cargo on the database referring to transactional. One have to be aware about the factors which can due to the fact the Micro ETL plans to produce incorrect facts.

In the case of the schemas that percentage a celeb hierarchical shape and while one representation is deleted from an assessment plan, the assignments may be inaccurate. An instance may be furnished on this context to strengthen this truth. If the truth desk of the person is refreshed on a frequent foundation whilst in comparison to the fact table of Revenue, the complete varieties of diagrams also can facilitate the production of outcomes which can be inconsistent. 

On the other hand, if someone deletes the table of dimensions from a Plans related to accomplishments related to ETL, the outdoor related to the tables of statistics could always factor to the unspecified rows. The key references could be solved in case the plans associated with accomplishments are being run on a DAC server. The customers of the reports mentioned facts warehousing need to be privy to various inconsistencies.

On the other facet, in case you do now not incorporate the tables of aggregates in the plans associated with execution, the data that typically utilizes facts might remain inconsistent. On the other hand, if the tables of totals are created from the program associated with performance, the plans about accomplishments are achieved for processes described to ETL. The tables of a hierarchy also are constructed in the occasion of each Plan associated with achievements associated with ETL. In case you avoid overfilling the counters throughout the ETL methods, the inconsistencies related to information could usually arise.

Question 14. Over All Architecture Of Dac?

Answer :

DAC server and DAC Client. They should co-discover with Informatica Integration provider, repository carrier and Informatica repository.

Question 15. Why We Should Use Dac And Not Control All Execution Through Informatica?

Answer :

For better overall performance control, along with growing index, losing index, truncating before load. Without DAC a custom ETL technique will be wished, which has to live to tell the tale the upgrate.

Oracle Data Guard Interview Questions
Question 16. Can We Run Multiple Execution Plan At The Same Time In Dac?

Answer :

Yes. Handiest if the execution plan aren't loading into the equal desk or using the equal phyiscal table source.

Question 17. Explain Dac Export/import?

Answer :

A way to import or export DAC repository metadata for improve or backup. Logical, System, runtime objects may be import/export.

Oracle Apps DBA Interview Questions
Question 18. Have You Change Any Of The Dac Parameters ? If So Which One And Why ?

Answer :

You need to recognize what are the DAC parameters and the purpose of every. For example, Initial_extract_date may be modified whilst configure for preliminary complete load, so the fee for initial extract date could be used to clear out facts from the supply which can be older than this date.

Oracle DBA Interview Questions
Question 19. How Do You Determine The Informatica Server Maximum Sessions Parameter Setting In Dac?

Answer :

One you sign up informatica server in Dac client.

Question 20. Can Dac Send An Email Just In Case Of Any Failures ?

Answer :

In DAC Client, toolbar, click e-mail recipient, then in Tools--> DAC Server setup, Email configuration.

Oracle Core Dba Interview Questions
Question 21. Can You Execute The Sql Scrip Through Dac ? If Yes How ?

Answer :

Yes, at challenge degree, in execution type, select SQL file. As an advantage to this answer, this article explains the way to run keep processes in DAC.

Question 22. In Dac How You Can Disable Table Indexes Before Loading And Enable The Index Once Load Is Complete ?

Answer :

Just drop and recreate index.

Question 23. Let Say You Are Running The Normal Incremental Load. But Just For Today You Want To Extract Data From Ap_invocies_all From 12/12/2011? How You Can Achieve This ?

Answer :

Modify the refresh date to be 12/12/2011.

Oracle D2K Interview Questions
Question 24. How Dac Determines The Order Of Task Execution Within An Execution Plan ?

Answer :

Based on duties source/target desk, Task phase (extract dim, load reality and many others) and 'truncate continually' properties, to run them in particular order, create mission group.

Oracle 11g Interview Questions
Question 25. What Are Micro Etl Execution Plans ? How Can You Build And Run Them ?

Answer :

According to Oracle record:

Micro ETL execution plans are ETL tactics which you schedule at very common periods, which includes hourly or half of-hourly. They typically take care of small problem areas or subsets of large problem regions. The DAC tracks refresh dates for tables in micro ETL execution plans one by one from different execution plans and uses those refresh dates inside the exchange seize method.

In layout -- concern regions, create replica of difficulty location, inactive the unwanted responsibilities and create new execution plan for this issue location.

Question 26. From You Past Experience – Explain Scenario Where Micro Etl Execution Plans Produced Wrong Results On Reports?

Answer :

According to Oracle Document:

CAUTION:  Micro ETL processes can reason issues with facts inconsistencies, facts availability, and extra load on the transactional database. Therefore, you need to 

recollect the subsequent factors before imposing a micro ETL method:

For associated star schemas, if one schema is left out from a micro ETL execution plan, the go-megastar reports can be faulty. For instance, if the Person reality table is refreshed greater regularly than the Revenue fact table, a report that spans the Person and Revenue dimensional schemas may also produce inconsistent outcomes.

If you miss dimension tables from a micro ETL execution plan, the foreign keys for the fact tables will point to Unspecified rows for the new measurement statistics. The foreign key references will be resolved when the Complete ETL execution plan is administered, but customers of the reviews must be aware about such inconsistencies.

If you do no longer encompass aggregate tables in micro ETL execution plans, the reports that use information from those tables might be inconsistent with the reviews that use records from the exact truth tables. However, if combination tables are included inside the micro ETL execution plan, the combination calculations are achieved for each ETL technique, that allows you to take a constant quantity of time and may be inefficient to perform at such frequent intervals.

Hierarchy tables are rebuilt all through every ETL execution plan through querying the bottom dimension tables. This operation takes a steady amount of time. If the base tables are big, this operation may additionally take a long time and may be inefficient if the micro ETL execution plan runs numerous instances an afternoon. However, if you keep away from populating the hierarchy tables in the course of micro ETL strategies, information inconsistencies will occur.

With micro ETL execution plans, caching will occur greater frequently, which may have performance implications.

Micro ETL execution plans will put greater load at the transactional database due to the frequent extracts.

Oracle 11g RAC Interview Questions
Question 27. Let Say You Can Not Use Dac Scheduler To Schedule You Execution Plan. What Other Options Do You Have ? How You Can Achieve This ?

Answer :

Use Informatica scheduler.

Oracle BPM Interview Questions
Question 28. Does Dac Keeps Track Of Refresh Dates For All The Source/goal Tables ?

Answer :

According to Oracle Document:

Refresh dates are tracked only for tables which are both a number one source or a number one target on obligations in a finished run of an execution plan. The DAC runs the whole load command for duties on which a desk is a number one supply or goal if the refresh date towards the desk is null. When there are multiple number one sources, the earliest of the refresh dates will trigger a full load or an incremental load. If anybody of the primary supply tables has no refresh date, then the DAC will run the whole load command.

Question 29. Can We Have Two Dac Server On The Same Machine ?

Answer :

You can run two DAC servers on the same device so long as they are listening on exclusive ports and pointing to 2 exceptional repositories.

Question 30. Explain Briefly What Kind Of Dac Repository Objects Held In Source System Containers ?

Answer :

Subject Areas -- A logical grouping of tables associated with a specific challenge or application context. It additionally includes the duties which are associated with the tables, 

as well as the duties required to load the tables. Subject regions are assigned to execution plans, which may be scheduled for full or incremental loads

tables -- Phsyical tables in DB

Indexes -- Just like your physical DB indexes

Tasks -- Unit of work for loading tables

Task businesses  ---- Grouping of tasks that may be bundled to run as a set

Execution plans -- A information transformation plans described on concern areas that needs to be converted at positive frequencies of time

Schedules -- Determine how often execution plan runs.

Question 31. What Is Authentication File ? If You Have Dac Client Installed Can You Access Dac Repository Without Authentication File ?

Answer :

According to Oracle Document:

When you configure a connection to the DAC Repository, the configuration method includes developing a new authentication report or deciding on an current authentication record. The authentication document authenticates the database in which the repository is living. If you create a new authentication record, you may specify the table proprietor and password for the database.

Question 32. Explain Index, Table And Task Actions In Dac ?

Answer :

According to Oracle Document:

Index movement: Override the default conduct for losing and growing indexes.

Table motion: Override the default conduct for truncating and analyzing tables.

Task motion: Can add new functionality of undertaking behavior, together with precedinf action, success movement, failure action, upon failure restart.

Question 33. How Dac Handles Parameters At Runtime ?

Answer :

According to Oracle Document:

During an ETL execution, DAC reads and evaluates all parameters related to that ETL run, which include static and runtime parameters defined in DAC, parameters held in flat files, and parameters described externally to DAC. DAC consolidates all of the parameters for the ETL run, deduplicates any redundant parameters, after which creates an individual parameter document for every Informatica session. This document carries the evaluated name-cost pairs for all parameters, both static and runtime, for each workflow that DAC executes. The parameter file contains a segment for each session underneath a workflow. DAC determines the classes below a workflow in the course of runtime with the aid of the use of the Informatica pmrep characteristic ListObjectDependencies.

The naming conference for the parameter document is

....Txt

DAC writes this record to a region specific within the DAC system assets InformaticaParameterFileLocation. The location exact by way of the assets informaticaParameterFileLocation ought to be similar to the vicinity specific via the Informatica parameter property $PMSourcefileDir.

Oracle BI Publisher Interview Questions
Question 34. How Dac Determines Tasks Required For Any Given Subject Area ?

Answer :

According to Oracle Document:

You outline a topic region with the aid of specifying a truth desk or set of reality tables to be the critical table or tables inside the concern vicinity. When a subject area is described,

DAC plays the following system to determine the relevant obligations:

DAC identifies the dimension tables associated with the facts and provides these tables to the difficulty place.

DAC identifies the related tables, which includes aggregates, related to the truth or measurement tables and provides them to the difficulty area definition.

DAC identifies the obligations for which the measurement and fact tables indexed inside the  procedures above are objectives tables and provides those duties into the difficulty vicinity.

Tasks that DAC automatically assigns to a subject place are indicated with the Autogenerated flag (inside the Tasks subtab of the Subject Areas tab).

You can inactivate a assignment from collaborating in a topic vicinity by using deciding on the Inactive check box (within the Tasks subtab of the Subject Areas tab). When the Inactive take a look at container is chosen, the undertaking stays inactive even in case you reassemble the situation place.

You can also do away with a assignment from a topic vicinity using the Add/Remove command inside the Tasks subtab of the issue Areas tab, but when you dispose of a venture it's far only removed from the difficulty vicinity till you reassemble the subject place.

DAC identifies the source tables for the tasks diagnosed inside the preceding procedure and adds these tables to the problem location.

DAC performs this process recursively until all essential obligations were introduced to the subject region. A mission is brought to the problem area only once, despite the fact that it's miles associated with numerous tables within the concern vicinity. DAC then expands or trims the total range of responsibilities based totally at the configuration guidelines, which are defined as configuration tags. This system can be aid in depth due to the fact DAC masses all of the objects within the source gadget field into memory before parsing.

Question 35. Difference Between Homogeneous And Heterogeneous Execution Plans?

Answer :

According to Oracle Document:

Homogeneous:

This sort of execution plan extracts records from a couple of times of the identical supply machine. For example, a enterprise would possibly have an instance of Oracle EBS 11i in a single region and time region and every other instance of Oracle EBS 11i in any other area and time zone. In such cases, the timing of statistics extraction from the one of a kind instances may be staggered to satisfy your business requirements.

Heterogeneous:

This form of execution plan extracts information from one or greater times of diverse source systems. For example, a enterprise would possibly have an instance of Siebel 7.Eight in a single location, an instance of Oracle EBS 11i in some other place, and a 2d instance of Oracle EBS 11i in but a 3rd place. You also can stagger the timing of statistics extraction while you use this sort of execution plan.