Upload
veerendra-katta
View
443
Download
1
Embed Size (px)
Citation preview
Veeren
dra K
atta
Concepts
1. What is a Data warehouse?
A Data warehouse is a denormalized database, which stores historical data in summary level format. It is specifically meant for heavy duty querying and analysis.
2. What is a Data mart?
A Data mart is a subset of a Data warehouse and is generally specific to a certain department or process, e.g. a finance data mart or a production data mart.
3. What are the various approaches of building a Data warehouse?
This is a generic question: From a business perspective, it is very important to first get clarity on the end user requirements and a system study before commencing any Data warehousing project. From a technical perspective, it is important to first understand the dimensions and measures, determine quality and structure of source data from the OLTP systems and then decide which dimensional model to apply, i.e. whether we do a star or snowflake or a combination of both. From a conceptual perspective, we can either go the Ralph Kimball method (build data marts and then consolidate at the end to form an enterprise Data warehouse) or the Bill Inmon method (build a large Data warehouse and derive data marts from the same. In order to decide on the method, a strong understanding of the business requirement and data structure is needed as also consensus with the customer.
4. What is OLAP?
OLAP is a multidimensional data structure from where we can view summary level information about a business, e.g. total sales in a year or total sales in a certain geography.
5. What is ETL?
ETL is a process of extracting data (OLTP data) from source systems and transforming them into dimensional models and storing the same in a Data warehouse. ETL also involves data cleansing and data manipulation, based on the nature of the business requirement. It is often a long process, which takes around 70‐80% time in a typical Data warehouse project.
6. What is the Difference between OLTP and OLAP?
OLTP refers to transactional data or data captured at the point of transaction, whereas, OLAP is a multidimensional representation of data which throws out summary level information.
7. What are the various Reporting tools in the Market?
To name a few‐ Cognos 8 BI, Business Objects Enterprise Edition, SQL Server Reporting Services, Oracle Discoverer, IBM DB2 Alphablox, Hyperion, Microstrategy, SAS, SAP BIW.
8. What is Metadata?
In simple words we can say that it is “data about data”. It stores all information about data like where it is stored, how it is stored, how it is formatted, address of the stored location, size of the data, ownership of data, created and modified time of data etc.
9. What is Staging Area?
Staging Area is a data holding place where the data which is extracted from the data sources is stored. Data is cleansed and temporarily stored here before it is loaded into the Data warehouse.
Veeren
dra K
atta
10. What is Factless Fact Table?
Factless fact table is nothing but a fact table which doesn’t have any measures.
11. What is slowly changing dimension?
It is nothing but a dimension which stores historical data as well as data which changes with time. For example, in an organization, there are two departments (Dep1 and Dep2) and employee1 is in Dep1. After completing the 1st year, employee1 got promotion to Dep2. Here the data item ‘department name’ of the ‘employee’ dimension is changed with respect to time.
12. What is a Surrogate key?
Surrogate key is a unique identifier. It is used to identify each row of a table uniquely. It also helps to track slowly changing dimensions. It replaces all natural keys. Surrogate keys are system generated keys, they are not derived from any data sources.
13. What is a Data source?
It is a place from where the data is extracted for the data warehouse. Data is Extracted, Transformed and Loaded to the data warehouse from the data source. The data source may be operational database, flat files, CSV (Comma Separated Values) files, VSAM (Virtual Storage Access method) files etc.
14. What is Virtual Data Warehousing?
It is the process of accessing the operational database directly by the end users for decision making purposes. But in traditional data warehousing systems, we load the data from the source to the target first and then we analyze it. In virtual data warehousing concept, data warehouse is a virtual entity.
15. What is the difference between star schema and snowflake schema?
The main difference between star schema and snowflake schema is that the star schema is highly denormalized and the snowflake schema is normalized. So the data access latency is less in star schema in comparison to snowflake schema. As the star schema is denormalized, the size of the data warehouse will be larger than that of snowflake schema. The schemas are selected as per the client requirements. Performance wise, star schema is good. But if memory utilization is a major concern, then snow flake schema is better than star schema.
16. What is Data Profiling?
Data Profiling is a process to find out the process information present in the source.The process or tool used for data profiling is called Data Discovery Phase.
17. What is a Junk Dimension?
A ‘junk’ dimension is a collection of random transactional codes, flags and/or text attributes that are unrelated to any particular dimension. Junk Dimension is just a dimension that stores unwanted attributes.
18. What is a Fact table?
It is a table which contains factual information of a business process. Fact table contains measures, foreign keys of all related dimension tables and attributes etc.
19. What is a Dimension table?
It is a table which contains categorized data. Eg: Time dimension, Products dimension etc.
Veeren
dra K
atta
20. What is fact constellation?
Fact constellation is also known as galaxy schema. It is nothing but a schema which contains multiple fact tables shares dimensions. It is a collection of star schemas which shares their dimension. So it is called as a galaxy schema.
21. What is cube?
Cube is a multidimensional representation of data. It is used for analysis purpose. A cube gives multiple views of data.
22. What is drill‐down and drill‐up?
Both drill‐down and drill‐up are used to explore different levels of dimensionally modeled data. Drill‐down allows the users view lower level (i.e. more detailed level) of data and drill‐up allows the users to view higher level (i.e. more summarized level) of data.
23. What is the need of building a data warehouse?
The need of building a data warehouse is that, it acts as a storage fill for a large amount of data. It also provides end user access to a wide varity of data, helps in analyzing data more effectively and also in generating reports. It acts as a huge repository for integrated information.
24. What is Data Modeling? What are the different types of Data Modeling?
Data modeling is a process of creating data models. In other words, it is structuring and organizing data in a uniform manner where constraints are placed within the structure. The Data structure formed are maintained in a database management system. The Different types of Data Modeling are: 1. Dimension Modeling 2. E‐R Modeling.
25. What are the different types of Data models?
Conceptual Data Model, Logical Data Model and Physical Data Model
26. What are the different types of OLAP TECHNOLOGY?
Online Analytical process is of three types, they are MOLAP, HOLAP and ROLAP. MOLAP – Mulidimensional online analytical process. It is used for fast retrival of data and also for slicing and dicing operations. It plays a vital role in easing complex calculations. ROLAP – Relational online analytical process. It has the ability to handle large amount of data. HOLAP – Hybrid online analytical process. It is a combination of both ROLAP and MOLAP.
27. What is the difference between a Database and a Data warehouse?
Database is a place where data is taken as base to data access to retrieve and load data, whereas, a data warehouse is a place where application data is managed for analysis and reporting services. Database stores data in the form of tables and columns. On the contrary, in a data warehouse, data is subject oriented and stored in the form of dimensions and packages which are used for analysis purpose. In short, we must understand that a database is used for running an enterprise but a data warehouse helps in how to run an enterprise.
28. What is a conformed dimension?
A dimension which is shared across two or more fact tables is known as conformed dimension. It is one of the key methods to join set of data marts into one consolidated data warehouse. It facilitates drill across process i.e. analysis of data across dimensions.
29. What is drill through?
It is a technique in which a user can see the underlying detail related to an aggregate. In this technique the analysis of the data traces its path from the OLAP cube into the relational database.
Veeren
dra K
atta
30. What is aggregation?
Aggregation is the summarization of information in the data warehouse. The advantage of aggregation is, it reduces the storage space and improves the performance of the queries.
31. What are non‐additive facts?
Non‐additive facts are the facts which cannot be summed up for any of the dimensions present in the fact table.
32. What is Data cleaning?
Data cleaning is the process of removing the errors, redundancies and the inconsistencies present in the source data before loading it into the data warehouse. It involves removing the null values, checking for consistency in the data format, standardizing date format, finding the missing values, eliminating or adding the title for a set of records and standardizing the numerical values.
33. What is data migration?
It is the transfer of data from one platform to another. This may include conversion from one language / file structure / operating environment to another. The migration of data happens when the data in the legacy systems is moved in to the data warehouse.
34. What is a legacy system?
It is the computer system which is in use from a long time. The data warehouse sources the data from different legacy systems which have different formats and are at times inaccurate
35. What is Data Quality Assurance?
It is a crucial process before loading the data into the data warehouse. It checks for the quality of the data which is being imported into the data warehouse. If data having errors is loaded into the data warehouse it will reflect in the final output by giving reports with error data.
36. What is Data transformation?
It is the process which applies a series of rules to manipulate the extracted data to suit the end user requirements. The data quality has to be improved before it becomes useable in the data warehouse. Some of the basic tasks performed in the transformation process are selection, splitting, joining, conversion, calculation, derivation and summarization of data.
37. What is Decision support system (DSS)?
A computer based decision making system used by the organizations in the 1980’s and 1990’s. The DSS is the ancestor of Business Intelligence.
38. What is Normalization?
Normalization is a process having a sequence of steps for creating relational database model. It increases granularity by removing duplication.
39. What is Hierarchy?
Hierarchy is the structuring of data in terms of a logical tree. This logical tree will have different levels depending on the detail of data. A location will have city, state and region as levels in its logical tree. The city forms the lowest level of detail with respect to the location.
Veeren
dra K
atta
40. What is a Hyper Cube?
Hyper Cube is a multidimensional cube with more than three dimensions. It is a single cube which stores all the data having application dimensions applied to it.
41. What is Logical extraction?
Logical extraction is the process in which data is extracted table by table. The data from the OLTP database is extracted without changing the existing table structure.
42. What is Partitioning?
Partitioning is a process of splitting physical data sets into smaller physical parts. Each physical part can be operated on individually or parallel processing on multiple partitions can take place. The smaller subsets of data & the parallel processing makes it comparatively faster than serial processing of very large data.
43. What is Granularity?
Granularity describes, upto what level of detail the measures are stored in the data warehouse. The data with the lowest level of granularity can be reshaped to meet different needs. Granular data can be easily summarized.
44. What are Normal Forms?
The sequence of steps involved in the Normalization process is known as Normal Forms. Commonly, first, second & third normal forms are applied. Followed by Boyce‐Codd, fourth, fifth & Domain Key normal forms in sequence, but these are rarely applied.
45. What is Denormalization?
Denormalization is a process which removes the granularity by introducing duplication & reducing the number of joins between entities.
46. What are the methods of loading data in Dimension tables?
There are two methods of loading data in dimension tables, namely: • Conventional Method • Direct Method Conventional Method: ‐ In this method before the data is loaded all the constraints and the corresponding keys are validated against the data to maintain the integrity. This is a time consuming method.. Direct Method: ‐ In this method before the data is loaded all the constraints and the corresponding keys are disabled. The data is validated against the constraints and keys after the loading takes place.
47. What is the difference between core dimension and conformed dimension?
Dimension table which is used by a single fact table is known as core dimension. Dimension table shared by two fact tables is called conformed dimension
48. What are dimensional attributes?
The attributes of the dimension are known as dimensional attributes. For example company dimension contains attributes like company id, company name.
50. What is logical model?
A Logical data model is a data model that represents the business requirements (entire or part) of an organization and is developed before the physical data model. Logical data model includes all required entities, attributes, key groups, and relationships that represent business information and defines business rules.
Veeren
dra K
atta
51. What is physical model?
Physical data model includes all required tables, columns, relationships, database properties for the physical implementation of databases.
53. What is modeling?
Modeling is the way to represent the organization’s need in effective way, it gives information to the users to understand the business rules and the processes involved.
54. What is business data?
Business data refers to the information in relation to operate a business like people, places, things, business rules, and events. It is very important to gather business data for analysis and to take precise decisions on how to bring the company forward.
57. What is Data tracking?
Data tracking involves tracing data from the point of its origin to its final state. Data tracking is very useful in a data warehouse implementation, since data warehouse is a complex system that involves data extracted from various operational data sources and data marts.
58. What is DATA BASE?
Database is a collection of data (any useful information) which can be accessed, modified, updated as and when required.
59. What is Atomic Data?
Data elements that represent the lowest level of detail are called atomic data. For example, in a daily sales report, the individual items sold would be atomic data.
60. What is Schema?
Structure for a database is known as schema. In a relational database, the schema defines the tables, the fields in each table, and the relationships between them.
61. What is a table?
It is a two dimensional object in a relational database, storing data in rows and columns. In a sales database, the database may contain Products Table, Orders Table, Customer Table and so on. The Products Table may contain columns ProductID, ProductName, ProductPrice.
62. What is a data type?
Data type is an attribute that specifies what type of data is to be stored into the column or a variable. It allows a column or a variable to hold only a specified type of data. It helps to store valid format of a data.
63. What is NULL?
Null is an entry that has not been assigned a value. NULL is not equivalent to zero or blank. A value of NULL is not greater than, less than, or equivalent to any other value, including another value of NULL.
64. What is ‘constraint’ in relational Databases?
Constraint is a property assigned to a column that prevents the entry of certain type of invalid data to that column. For example, PRIMARY KEY CONSTRAINT in a column prevents getting duplicate or NULL values into that column.
Veeren
dra K
atta
65. What are triggers?
Triggers are the special kind of procedures created and saved in Databases that will be invoked automatically when the database events are fired. Database events could be the insertion, deletion or updation of records or creation, altering or dropping of other database objects. There are Data Manipulation Language and Data Definition Language Triggers.
66. Which modeling do we use in Data Warehouse?
Dimensional Modeling is used in data warehouse. It contains dimensions and fact tables.
67. What is DBMS?
DBMS stands for Database Management System; it is a set of software used to manage databases. It is used to store, manage, and retrieve the data from databases.
68. What are different types of data mart?
This classification is based on the data source used to create a data mart. There are 3 types of data mart Independent data mart Dependent data mart Hybrid data mart Dependent data marts draw data from a central data warehouse that has already been created. Independent data marts, draws data directly from operational data source Hybrid data marts can draw data from operational systems or from data warehouses.
69. What is Connection string?
Connection string is used by an application to make connection through network. This string includes the information like which object to be connected, and where exactly it is located and the authentication details to make connection.
70. What is Candidate key?
Candidate Key is a column or a set of columns available in a table which allows distinct values and not null values. A table can have any number of candidate keys. From the available keys, one key will be selected and set as primary key.
71. What is the different types of modeling?
There are two different types of modeling: 1. Business modeling. 2. Data modeling.
72. What are the different types of business modeling?
The different types of Business Modeling are: 1. Process Flow Modeling: is used to describe the processes that happen in an organization. It is also called Work Flow Modeling. 2. Business Process modeling: is used to analyze the business processes 3. Data Flow Modeling: it defines the flow of data between different business processes, it explains all the activity involved in the business processes.
73. What is meant by Business Process Management?
Business Process Management helps to monitor the activities of a business which in turn helps the organization to grow.
74. What is the need for Business Process Management?
Business Process Management helps to document the business processes in a language which can be understood by all team members. It also helps to plan for a new business or for any change in the existing business.
75. What is meta‐data text repository?
Meta‐data text repository is used by ETL clients, and it is a faster and better environment that provides better support for multiuser sharing the model.
Veeren
dra K
atta
76. What is a transaction?
Transaction is a single or group of operations performed in a database. For example, withdrawal of cash transaction includes only one operation of updating the present balance of a single account; whereas the Fund Transfer transaction includes multiple operations since multiple accounts need to be updated.
77. What is Atomic Property in transaction management?
According to the Atomic Property either the transaction is executed completely or it is not executed at all. Suppose a transaction is half the way in its process, there are chances of some external failures like system crash or software/network failure. Here, atomic property ensures that; if these kinds of failures occur, the database system should have the ability to rollback the transaction to its previous stage.
78. What is Concatenation?
Concatenation is the operation of combining more than one character strings or binary strings into a single character string or binary string. For example EmployeeFirstName (Asish) and EmployeeLastname (Mehra) are combined to get EmployeeFullName (Asish Mehra).
79. What is a computed column?
It is a virtual column in a table whose value is calculated at run‐time. For this, it is required to define an expression for the computed column. For example, for sales computed column, the expression could be productprice*quantity.
80. What is the use of cursor?
Cursor is used to do fetch the records one by one or as a batch from a result set. Once cursor is positioned on one row of a result set, we can perform operations on it. It is mainly used to retrieve the row.
Cognos 1. What is the BI tool from Cognos?
Cognos 8 BI
2. What are the components of Cognos Reportnet?
Framework Manager(for meta data modeling), Query Studio, Report Studio, Event Studio and Metric Studio.
3. What is Cognos Connection?
It is a portal which has all the Cognos components visible‐ The components include Query Studio, Report Studio, Event Studio, Analysis Studio and Metric Studio. Users can select one or many among these options.
4. What is the Reportnet equivalent in latest version of Cognos 8?
It is called Cognos 8 BI
5. What is Cognos Data manager?
It is the ETL component from the Cognos stack.
6. What happened to Power play?
Powerplay has now been integrated as part of Cognos 8 BI and is now called as Analysis Studio.
7. What is the difference between Consumer and Recipient?
Consumer can run, view and perform drill down/up, slice and dice functions, whereas, recipient can only view reports.
Veeren
dra K
atta
8. What is the difference between Query Studio and Report Studio?
Query Studio is used to create ad hoc and simple reports, whereas, Report Studio is meant to run advanced and customized reports.
9. How do we utilise Java Script within Cognos?
There is an option within Cognos where we can embed Java scripts to customize the look and feel of the reports created in Cognos.
10. What is a Prompt?
A Prompt is a kind of filter which allows the user to select the required value which has to be filtered.
11. How many prompts are available in Cognos Report Studio?
There are nine prompts in Report Studio. They are: • Textbox prompt • Value prompt • Select and Search prompt • Date prompt • Time prompt • Date & Time prompt • Interval prompt • Tree prompt • Generated prompt
12. What is Generated prompt?
Generated prompt is a kind of prompt which automatically chooses and displays any of the other prompts at runtime according to the data type of the data item added for filtering. For example, if you add date and time value as the filtering item in a generated prompt, the prompt will automatically choose the ‘date and time prompt’ at run time.
13. What is a catalog in Data Manager?
Catalog is a work space which holds the components that define how Data Manager Extracts, Transforms and Delivers data to the target. It contains information regarding the data flow from data source to data warehouse. Catalog is stored in a separate database.
14. Which is the scorecarding tool of Cognos 8 BI?
It is called Metric Studio.
15. What is conditional block?
A conditional block is a block which gets executed based on the input given by the user at run time.
16. What is cascading prompt?
It is a prompt which makes use of the values from the previous prompt to filter the values in the current prompt.
17. What is the use of connection in Data Manager?
In Data Manager, a connection is used to establish a link to a database. The database may be source or target database.
18. What is the purpose of creating dimension builds in Data Manager?
Dimension builds are used to deliver dimensions to the target database. In Data Manager we can create dimension builds manually as well as through wizard.
19. What is query calculation in Report Studio?
It is a component inside the ‘Insertable Object’ pane of Report Studio. It is used to insert a calculated item into a report. For example, we can use query calculation to calculate the revenue by multiplying quantity into price.
20. What is the purpose of SQLTerm in Data Manager?
SQLTerm is used to construct SQL statements and also to test the result set obtained from the source database.
Veeren
dra K
atta
21. What do you mean by DataStream in Data Manager?
DataStream maps gather all data sources (from which the build acquires data) to the Transformation model/fact table.
22. What is a build?
Build is a Data Manager process that delivers required source data to the target warehouse/mart.
23. What is a namespace in Framework Manager?
Namespace uniquely identifies Framework Manager Objects like query subjects, query items, dimensions, etc.
24. Why should we publish a package in Framework Manager?
It is necessary to publish a package for report authors to create reports in Report Studio and for business authors to create ad hoc reports in Query Studio.
25. What is a Query Item?
Query Item represents a column of a table in the source database.
26. What is a Query Subject?
Query Subject is an SQL expression that represents the selected query items to be retrieved from the database.
27. What is MDX?
Multidimensional Expression (MDX) language is the multidimensional equivalent of SQL.
29. What does the Content Manager do?
Content Manager is a Cognos service that manages the storage of configuration data, reports and scheduling information.
30. What is Report Layout?
Report Layout defines the structure and the look‐and‐ feel of reports.
31. Why do we need object‐based security in Framework Manager? Where is the feature located?
Using object‐based security, we can make an object visible to selected users, groups and roles. It is located in the menu Actions‐> Specify Object Security.
32. How is Object Security different from Data Security?
Object security allows or denies user access to objects, whereas, Data Security controls what data the end user sees when a report is run.
33. How to import tables in relational database into Framework Manager project?
Click on the folder you want to import the tables into and in the Actions menu, click Run Metadata Wizard. Follow the instructions in the Metadata Wizard.
34. What is a governor and how do you set it?
A governor is a set of rules that controls user activities like data retrieval, query execution limit, usage of local cache etc. Governors can be set in Project menu‐> Edit Governors.
Veeren
dra K
atta
35. What is Explorer tab?
The explorer tab shows the content of a project similar to any file system. Objects can be arranged by name, class or description.
36. What is the diagram tab?
The diagram tab uses a diagram to show the relationship between objects in a project.
37. What is dimension map tab?
Dimension map tab is used to view, create and modify hierarchies and levels for the dimension that is selected in the project viewer.
38. What is the properties pane?
The properties pane shows the properties of the object that is selected in the project viewer, explorer tab, diagram tab, dimension map tab, Search pane or summary pane.
39. What is the summary pane?
The summary pane shows the language, statistics and tasks available for an object that we select in the project viewer.
40. What are macros?
Macros are fragments of code that we can insert anywhere in the select statement that defines a query subject.
41. What are data retrieval limits?
The data retrieval limits is a governor on setting which helps to control the number of rows that are returned in a query or report.
42. Expand BLOBS?
BLOBS stands for Binary Large Objects.
43. When do ambiguous relationships occur?
Ambiguous relationships occur when the data represented by a query subject or a dimension can be viewed in more than one context or role.
44. Which are the most common ambiguous relationships?
The most common ambiguous relationships are a) Multiple valid relationships b) Reflexive and recursive relationships.
45. What is the use of ‘object security’ in Framework Manager?
It is used to protect the specific objects like folders, namespaces, query subjects, query items and filters from the unwanted users. Using object security, we can restrict users and groups from accessing particular objects.
46. What is bursting report?
It is the process of creating a single report which will send different reports to different end users at the time of execution. For example, if we create a report which shows sales details made by different sales executives, it will send different reports to different regional managers at the time of execution. Each regional manager will get only the details of sales executives that come under his region.
Veeren
dra K
atta
47. What is a package?
A package is container which holds the items like reports, models created in framework manager etc. It is used to publish the models created in framework manager to the Reportnet Server.
49. What is report specification?
It is the XML representation of a report.
50. What is a regular dimension?
A regular dimension provides descriptive and business key information. It also organizes the information in a hierarchy from the highest to the lowest level of granularity.
51. What is the use of “_business key” role?
The “_business key” role represents the key of the level. It also helps to drill from one data source to another. This role can be assigned to only one attribute in a level.
52. What is the use of scope relationship?
The measure dimensions and regular dimensions can be related for reporting purposes by setting scope relationship.
53. What are determinants?
The determinants are a set of query items that uniquely identify a set of data.
54. What is native sql?
Native sql is the sql which is used by the data source.
55. How do we improve the speed of retrieval of data when running a report?
The speed can be improved by reusing the cached data.
56. How do we reuse the Cached data?
When a report runs, the request is sent to data base. The data is then retrieved and stored in a cache. To reuse the cached data, we have to enable the “Allow Usage of Local Cache” governor on model in framework manager and then publish the package.
57. What is the use of governors?
Governors reduce system resource requirements and improve the performance.
58. What are the benefits of nested packages?
The package can be reused by creating nested packages. Nested package saves time and it is easy to maintain. Only the master package needs to be published in nested packages.
59. What are the methods available to externalize query subjects in framework manager?
a) csv b) tab b) iqd c) embedded
60. What is a materialized view?
A materialized view materializes the data i.e., it stores the data physically separate from the tables. It provides indirect access to table data by storing the results of a query in a separate schema object.
Veeren
dra K
atta
61. What is a template?
A template defines the attributes and their behaviors for a dimension table. We require a template to properly maintain and use the corresponding reference dimension table.
62. How job streams are useful?
Job streams automate the execution. It is used to group other components into logical processes so that the execution can be automated.
63. What is a fact build?
A fact build specifies how to acquire, transform and deliver fact and reference data.
64. What are IQD files?
IQD stands for Impromptu Query Definition. IQD method externalizes a query subject to use in transformer or other applications.
65. What is the difference between regular dimension and measure dimension?
A regular dimension contains descriptive and business key information. It also organizes the information in a hierarchy, from the highest level of granularity to the lowest. A measure dimension is a collection of facts. We can create a measure dimension for one or more query subjects that have a valid relationship between them.
66. What is the benefit of using portal tabs?
The portal tabs in cognos 8 connection helps access the pages that are important.
67. What is a job?
A job identifies a collection of reports, report views and other jobs that are scheduled together. They share the same schedule settings.
68. What is a deployment archive?
A deployment archive is a compressed file that contains the actual entries that are deployed.
69. What is a model?
A model is a data structure containing imported data from one or more data sources.
70. What is a portlet?
A portlet is a mechanism for displaying web content as part of a portal page.
71. What are isolation levels?
The isolation level specifies how to handle the transactions that modify the database.
72. Mention the isolation levels.
The following are the isolation levels. a) Read uncommitted b) Read committed c) Cursor Stability d) Reproducible Read e) Phantom protection f) Serializable
73. How are “roles” different from “groups”?
In Cognos 8, groups and roles represent collection of users that perform similar tasks or the users with similar status. A group membership is a part of the user’s basic identity. Members of the groups can be users and other groups. On the other hand, a role membership is not the user’s basic identity. The member of roles can be a user, group or other roles.
Veeren
dra K
atta
74. What are the uses of trusted credential?
The trusted credentials are used for users who perform a task or process, but do not have sufficient access permissions for accessing sensitive data such as database signons and group membership. The trusted credentials are also used to run scheduled requests when users are not logged on to cognos 8.
75. What is the full form of XSS?
The full form of XSS is cross‐site scripting.
76. How do we improve the speed of retrieval of data when running a report?
The speed of retrieval of data can be improved by reusing the cached data.
77. How do we reuse the Cached data?
When a report runs, the request is sent to data base. The data is then retrieved and stored in a cache. To reuse the cached data, user has to enable the “Allow Usage of Local Cache” governor on model in framework manager and then publish the package.
78. What is the use of governors?
Governors reduce system resource requirements and improve the performance.
79. What are the benefits of nested packages?
The package can be reused by creating nested packages. Nested package saves time and it is easy to maintain. Only the master package needs to be published in nested packages.
80. What are the methods available to externalize query subjects in framework manager?
a) CSV b) TAB b) IQD c) Embedded
81. What are the different types of security in framework manager?
In framework manager there are different types of security they are a) Data security b) Object security c) Package security.
82. What are the files that are created when a Framework Manager project is created?
.cpf, Model.xml, preferences.xml, customdata.xml and repository.xml are the files that are created when a project is created in Framework Manager, and they reside in the project folder.
84. What is synchronization in framework manager?
Synchronization in frame work manager is the replaying from the log file, all the actions that are made in the original project.
85.When the synchronization is useful in framework manager?
Synchronization is used to get updated metadata into the project 1) When the metadata is updated from a third party tool. 2) When there is change in metadata using a multidimensional modeling tool.
86. What is meant by Dual Display?
In Power play user can create reports that can be simultaneously viewed in the crosstab and the chart form in single report. It is known as Dual Display.
Veeren
dra K
atta
87. What is meant by Levels?
Dimensions are made up of levels, which represents hierarchy within the dimensions.
88. When are Reporter Report used in Power Play Transformer?
Reporter Reports are used when there is exact information to add to a report and calculations are to be performed in the Power Play Transformer.
89. Explain the use of Explorer Reports.
Explorer Reports are used to explore the information in the cube. Here, the information can be displayed as percentage of the row or grand total.
90. What is the use of Graph Reports?
Graph Reports display comparisons, relationships and trends. They are generally used when there is a large amount of data in cross tab.
SQL Server
1. What is the ETL component of SQL Server 2005?
It is called SSIS or SQL Server Integration Services.
2. What is the Reporting component of SQL Server 2005?
It is called SQL Server Reporting Services.