MSBI Interview Questions and Answers
by sonia, on May 26, 2017 4:28:17 PM
These Interview Questions Involves Microsoft BI(SSIS,SSAS,SSRS)
Q1. MSBI Characteristics
Ans:
Criteria | Result |
Analytics | Dashboards, guided navigation and drill down |
Type of Solution | End-to-end Business solution with extended ETL |
User-friendly | Ease of installation, use, maintenance |
Get a detailed understanding of the advantages of MSBI over other business intelligence tools.
Q2. Define Query parameter in SSRS?
Ans:
Query parameters is revealed in the query of the datasources that are to be included into the SQL script’s where clause of the SQL that can accept parameters. Query parameters begin with the symbol @.
Q3. What are the Reporting Service Constituents in SSRS?
Ans:
A.Report Manager :A Web-based administration tool for managing the Report Server.
B Report Server : Provides services for implementation and delivery of reports.
C. Report Designer : A place where we can create report.
Q4 What do you understand by matrix in SSRS?
Ans: A matrix is a data region related to a report set. Matrix permits us to create crosstab reports with the report variables showing on rows and columns. It allows us to drag.
Q5. What do you mean by sub reports and how we can create them?
Ans: A sub report is like any other reports which can be termed in main report and can be generate through main report. Parameters can be conceded from main report to sub report and basis of that report can be created.
Q6. Define report model project?
Ans: Report model project is used for creating Adhoc reporting. We can create the adhoc reports over report builder. Report model project can be created on bids or report server. This model can have simple view.
Q7. What do you understand by report server project?
Ans: Report Server Project comprises of RDL file and it need to be deployed on report server to view the report files to application and user. It is a solution where we can design our reports. We can add it by going into BIDS clicking on new item and then selecting reports server project. Once the solution is formed we can start forming reports.
Q8. Explain report builder?
Ans: Report builder is used to create small reports and it is a define interface. We can’t change the report interface in report builder it pre designed. We can just drag columns in the report. It creates reports on database objects available with report model project.
Q9. In which SQL Server type report builder introduced?
Ans: Report builder presented in SQL Server 2005. While creating or arranging report model project on report server we can get error or it might not get formed. For this we need to check whether the service pack 22 is installed or not.
Q10. How to organise the Report?
Ans:
Report can be organized in three ways :
- Using visual studio :In visual studio we can directly deploy the report through solution explorer by providing the report server URL in project properties at Target Server URL. This will organize entire project or single report as per our selection.
- Using report server :We can directly go to the report server and deploy the report by looking the report from the disk location on server.
- Creating the utility :SQL server provides the utility which can be used to create a modify utility for our report deployment in bulk.
Q11. Define RS.exe utility?
Ans: Rs.exe utility is used for organizing the report on report server. It comes with the report server and can be modify accordingly.
Q12. What is the name of reporting services config file and what it is used for?
Ans: Reporting service config file is used for report configuration details. It contains the report format and also the report import types. Report service config exist in ISS.
Q13. What are the three different part of RDL file elaborate them?
Ans: In visual studio RDL files has three parts.
- Data :It covers the dataset on which we write the query. Data set is associated with data source.
- Design :In design we can design report. We can create tables and matrix reports. We Drag columns values from source.
- Preview :It ia used to check the preview after the report run.
Q14. Which language rdl files made of?
Ans: RDL files are printed in XML.
Q15. What do you understand by chart in report?
Ans: Chart reports are for graphical representation. We can get pie charts columns harts and various other options. 3d charts are also presented in reporting services.
Q16. Define Data Set in report?
Ans: Data set are the set of data which we want to show in report. Data creates on data source. Data source is the source of data from where we are receiving this data i.e. database server and database name joining string.
Q17. Name different types of data sources in SSRS?
Ans: SSRS use different data source. Some of them are listed below.
- SQL Server SAP Net weaver BI.
- Report Server Model.
- SQL Server Analysis Service OLEDB.
- SAP Net weaver BI.
- XML
Q18. What is the web service used for reporting services?
Ans: Reporting Service Web Service used in SSRS. By retrieving this web service we can access all report server section and also get the report organized on report server.
Q19. How to enhance the custom code in Report?
Ans: To enhance the custom codes in report go to report tab on top then properties and there you will find the selections for custom code.
Q20. Define cache in SSRS?
Ans: Report server can lay up a copy of processed report in a memory and return the copy when a user opens the report. This server memory is called as cache and the process is known as caching.
Q21. Elaborate Web service task in SSIS?
Ans:
- First we configure HTTP Connection manager which will point to WSDL of a web service.
- Web service task customs this HTTP Connection manager and let us invoke methods in it.
- It return values of method value we can store it in some variables and can use as input for some other tasks.
Q22. Explain transfer SQL Server object task?
Ans: It allows us to allocate different SQL server objects between different instances of SQL Server.Object incomes from table, stored procedures, user defined functions etc.
Q23. In SSIS is it conceivable to communicate with MSMQ?
Ans: Yes, it is possible for that we have Message Queue task. It contract us send messages to MSMQ and receive message from MSMQ.
Q24. What is the advantage of using MSMQ?
Ans: MSMQ helps in communicating two applications with each other asynchronously. Specialty is two application may be built using dissimilar technology and it works even offline messaging. Sender will stock messages inside queue and reader reads it wherever required.
Q25. What are the Different Lookup Cache Modes Available in SSIS?
Ans:
There are basically 4 Cache Modes available in SSIS Lookup Transformation
- Full Cache Mode.
- Partial Cache Mode.
- No Cache Mode.
- Full Cache Mode
Q26. Differentiate between SSRS 2005 and SSRS 2008
Ans: The major differences between SSRS 2005 and SSRS 2008 are as follows:
SSRS 2005 report server requires IIS, whereas SSRS 2008 comes with a build-in web server and hence does not require IIS.
Q27. Explain architecture of SSIS?
Ans:
SSIS architecture involves four key parts :
- a) Integration Services service :
It monitors running Integration Services packages and accomplishes the storage of packages. - b) Integration Services object model :
It contains managed API for reading Integration Services tools, command-line utilities, and custom applications. - c) Integration Services runtime and run-time executables :
It keeps the layout of packages, runs packages, and provides support for logging, breakpoints, configuration, connections, and transactions. - d) Data flow engine :
It provides the in-memory buffers that move data from source to destination.
Q28. How we can do Logging in SSIS?
Ans: Logging Configuration provides an inbuilt feature which can log the detail of various events like onError, onWarning etc .
Q29. How we can do Error Handling?
Ans: SSIS package contain mainly have two types of errors :
a) Procedure Error : It can be handled in Control flow bythe precedence control and redirecting the execution flow.
b) Data Error : it is handled in DATA FLOW TASK by redirecting the data flow using Error Output of a component.
Q30. How we can pass property value at Run time?
Ans: A property value like connection string for a Connection Manager can be passed to the pkg using package configurations.
Q31. How can we organize a SSIS Package on production?
Ans:
A)Through Manifest we can organize it :
- Create deployment utility by setting its properties as true .
- It will be formed in the bin folder of the solution once package is build.
- Copy all the files in the utility and use manifest file to display it on the Prod.
B) Using DtsExec.exe utility.
C)Import Package directly in MSDB from SSMS by logging in Integration Services.
Q32. Define Execution Tree?
Ans: Execution trees demonstrate how package uses buffers and threads. At run time, the data flow engine breaks down Data Flow task operations into execution trees.
Q33. Differentiate between Unionall and Merge Join?
Ans:
- a) Merge transformation can take only two inputs whereas Union all can take more than two inputs
b) Data has to be sorted before Merge Transformation whereas Union all doesn’t have any boundation like that.
Q34. How we can restart package from previous failure point? Define Checkpoints and how they are implement in SSIS?
Ans: When a package is arranged to use checkpoints, material about package execution is written to a checkpoint file. When the failed package is rerun, the checkpoint file is used to restart the package from the point of failure. If the package runs effectively, the checkpoint file is deleted, and then re-created the next time that the package is run.
Q35. Where do you store SSIS package in the SQL Server?
Ans: MSDB.sysdtspackages90 stores the original content .
Q36. What are the three stages of Enterprise Reporting Life Cycle ?
Ans: Authoring Stage: Creating Reports
Managing Stage: Managing Reports and Other Items
Delivery Stage: Accessing and Delivering Reports
Q37. What are the apparatuses included in SSRS?
Ans: A Complete set of Tools that can be used to generate, succeed and view reports.
- A Report Server component that hosts and processes reports in many formats. Output formats include HTML, PDF and more.
- An API that allows developers to mix or spread data and report processing in custom applications, or create custom tools to build and manage reports.
Q38. What are the benefits of using embedded code in a report?
Ans:
The benefits are:
- Reuseability of Code: function created in embedded code to achieve a logic can be then used in manifold expressions
- Centralized code: it helps in better manageability of code.
Q39. Which programming language can be used to code embedded functions in SSRS?
Ans: Visual Basic .NET Code is used to code embedded fuctions in SSRS.
Q40. What important terms can be used in the reporting services?
Ans:
- Report definition: A report definition contains information about the query and layout for the report.
- Report snapshot: A report snapshot is actually a report definition that contains a dataset instead of query instructions.
- Rendered report: A fully processed report that contains both data and layout information, in a format suitable for viewing (such as HTML).
- Parameterized report: A published report that accepts input values through parameters.
- Shared data source: A predefined, standalone item that contains data source connection information.
- Shared schedule: It is a predefined, standalone item that covers schedule information.
- Report-specific data source: Data source information which is defined within a report definition.
- Report model: A semantic description of business data, used for ac hoc reports created in Report Builder.
- Linked report: It is a report that derives its definition through a link to another report.
Q41. What are the Command Line Utilities available in Reporting Services?
Ans:
- Rsconfig Utility (Rsconfig.exe): encrypts and stores connection and account values in the RSReportServer.config file.
- RsKeymgmt Utility: it is used to Extracts, restores, creates, and deletes the symmetric key used to protect sensitive report server data against unauthorized access
- RS Utility: this utility is mainly used to automate report server deployment.
Q42. How we can know Report Execution History?
Ans: We can know Report Execution History as the execution log table in report server database contains all the logs from the last two months so we can see it from there.
Select-from reportserver.dbo.ExecutionLog
Q43. Differentiate between Tablular and Matrix report?
Ans:
- Tablular report: It is the most basic type of report. Each column corresponds to a column selected from the database.
- Matrix report: A matrix report is a cross-tabulation of four groups of data:
One group of data is displayed across the page.
b. One group of data is displayed down the page.
c. One group of data is the cross-product.
d. One group of data is displayed as the “filler” of the cells.
Q44. How we can create Drill-through reports?
Ans: By Using Navigation property of a cell and scenery child report and its parameters in it we can create Drill-through reports.
Q45. How to create Drill-Down reports?
Ans:
- By grouping data on essential fields
- Then toggle reflectivity based on the grouped filed
Q46. How we can schedule a SSIS packages?
Ans: Using SQL Server Agent we can schedule a SSIS packages.
Q47. Define Asynchronous transformation?
Ans: Asynchronous transformation have various Input and Output buffers and it is up to the component designer. It provide a column structure to the output buffer and hook up the data from the input.
Q48. How we can achieve parallelism in SSIS?
Ans: Parallelism is achieved using MaxConcurrentExecutable stuff of the package. Its default is -1 and is calculated as number of computers + 2.
Q49. How we can do incremental load?
Ans: Accurate and fastest way to do incremental load is by using Timestamp column in source table and then storing last ETL timestamp.
Q50. How we can handle Early Arriving Facts.
Ans: Early Arriving Facts sometime get unavoidable because delay or error in Dimension ETL or may be due to logic of ETL. To handle Early arriving Facts, we can create dummy Dimension with natural/business key and keep rest of the attributes as null or default.
Q51. Define SQL Server Reporting Services(SSRS)?
Ans: SQL Server Reporting Services is a server-based reporting platform that we can use to create and manage tabular, matrix, graphical, and free-form reports that contain data from relational and multidimensional data sources.
SSIS
Q52. What is SSIS? How it is related with SQL Server.
Ans: SQL Server Integration Services (SSIS) is a component of SQL Server which can be used to perform a wide range of Data Migration and ETL operations. SSIS is a component in MSBI process of SQL Server.
This is a platform for Integration and Workflow applications. It is known for a fast and flexible OLTP and OLAP extensions used for data extraction, transformation, and loading (ETL). The tool may also be used to automate maintenance of SQL Server databases and multidimensional data sets.
Q53. What are the tools associated with SSIS?
Ans: We use Business Intelligence Development Studio (BIDS) and SQL Server Management Studio (SSMS) to work with Development of SSIS Projects.
We use SSMS to manage the SSIS Packages and Projects.
Q54. What are the differences between DTS and SSIS
Ans:
Data Transformation Services | SQL Server Integration Services |
Limited Error Handling | Complex and powerful Error Handling |
Message Boxes in ActiveX Scripts | Message Boxes in .NET Scripting |
No Deployment Wizard | Interactive Deployment Wizard |
Limited Set of Transformation | Good number of Transformations |
NO BI functionality | Complete BI Integration |
Q55. What is a workflow in SSIS 2014 ?
Ans: Workflow is a set of instructions on to specify the Program Executor on how to execute tasks and containers within SSIS Packages.
Q56. What is the control flow?
Ans: A control flow consists of one or more tasks and containers that execute when the package runs. To control order or define the conditions for running the next task or container in the package control flow, we use precedence constraints to connect the tasks and containers in a package. A subset of tasks and containers can also be grouped and run repeatedly as a unit within the package control flow. SQL Server Integration Services (SSIS) provides three different types of control flow elements: Containers that provide structures in packages, Tasks that provide functionality, and Precedence Constraints that connect the executables, containers, and tasks into an ordered control flow.
Q57. What is the data flow?
Ans: Data flow consists of the sources and destinations that extract and load data, the transformations that modify and extend data, and the paths that link sources, transformations, and destinations The Data Flow task is the executable within the SSIS package that creates, orders, and runs the data flow. A separate instance of the data flow engine is opened for each Data Flow task in a package. Data Sources, Transformations, and Data Destinations are the three important categories in the Data Flow.
Q58. How does Error-Handling work in SSIS
Ans: When a data flow component applies a transformation to column data, extracts data from sources, or loads data into destinations, errors can occur. Errors frequently occur because of unexpected data values.
Type of typical Errors in SSIS:
-Data Connection Errors, which occur incase the connection manager cannot be initialized with the connection string. This applies to both Data Sources and Data Destinations along with Control Flows that use the Connection Strings.
-Data Transformation Errors, which occur while data is being transformed over a Data Pipeline from Source to Destination.
-Expression Evaluation errors, which occur if expressions that are evaluated at run time perform invalid
Q59. What is environment variable in SSIS?
Ans: An environment variable configuration sets a package property equal to the value in an environment variable.
Environmental configurations are useful for configuring properties that are dependent on the computer that is executing the package.
Q60. What are the Transformations available in SSIS?
Ans:
AGGREGATE - It applies aggregate functions to Record Sets to produce new output records from aggregated values.
AUDIT - Adds Package and Task level Metadata - such as Machine Name, Execution Instance, Package Name, Package ID, etc..
CHARACTERMAP - Performs SQL Server column level string operations such as changing data from lower case to upper case.
CONDITIONALSPLIT– Separates available input into separate output pipelines based on Boolean Expressions configured for each output.
COPYCOLUMN - Add a copy of column to the output we can later transform the copy keeping the original for auditing.
DATACONVERSION - Converts columns data types from one to another type. It stands for Explicit Column Conversion.
DATAMININGQUERY– Used to perform data mining query against analysis services and manage Predictions Graphs and Controls.
DERIVEDCOLUMN - Create a new (computed) column from given expressions.
EXPORTCOLUMN– Used to export a Image specific column from the database to a flat file.
FUZZYGROUPING– Used for data cleansing by finding rows that are likely duplicates.
FUZZYLOOKUP - Used for Pattern Matching and Ranking based on fuzzy logic.
IMPORTCOLUMN - Reads image specific column from database onto a flat file.
LOOKUP - Performs the lookup (searching) of a given reference object set against a data source. It is used for exact matches only.
MERGE - Merges two sorted data sets into a single data set into a single data flow.
MERGEJOIN - Merges two data sets into a single dataset using a join junction.
MULTICAST - Sends a copy of supplied Data Source onto multiple Destinations.
ROWCOUNT - Stores the resulting row count from the data flow / transformation into a variable.
ROWSAMPLING - Captures sample data by using a row count of the total rows in dataflow specified by rows or percentage.
UNIONALL - Merge multiple data sets into a single dataset.
PIVOT– Used for Normalization of data sources to reduce analomolies by converting rows into columns
UNPIVOT– Used for denormalizing the data structure by converts columns into rows incase of building Data Warehouses.
Q61. How to log SSIS Executions?
Ans: SSIS includes logging features that write log entries when run-time events occur and can also write custom messages. This is not enabled by default. Integration Services supports a diverse set of log providers, and gives you the ability to create custom log providers. The Integration Services log providers can write log entries to text files, SQL Server Profiler, SQL Server, Windows Event Log, or XML files. Logs are associated with packages and are configured at the package level. Each task or container in a package can log information to any package log. The tasks and containers in a package can be enabled for logging even if the package itself is not.
Q62. How do you deploy SSIS packages?
Ans: SSIS Project BUILD provides a Deployment Manifest File. We need to run the manifest file and decide whether to deploy this onto File System or onto SQL Server [ msdb]. SQL Server Deployment is very faster and more secure then File System Deployment. Alternatively, we can also import the package from SSMS from File System or SQL Server.
Q63. What are variables and what is variable scope?
Ans: Variables store values that a SSIS package and its containers, tasks, and event handlers can use at run time. The scripts in the Script task and the Script component can also use variables. The precedence constraints that sequence tasks and containers into a workflow can use variables when their constraint definitions include expressions. Integration Services supports two types of variables: user-defined variables and system variables. User-defined variables are defined by package developers, and system variables are defined by Integration Services. You can create as many user-defined variables as a package requires, but you cannot create additional system variables.
Q64. Can you name five of the Perfmon counters for SSIS and the value they provide?
Ans:
- SQLServer:SSIS Service
- SSIS Package Instances
- SQLServer:SSIS Pipeline
- BLOB bytes read
- BLOB bytes written
- BLOB files in use
- Buffer memory
- Buffers in use
- Buffers spooled
- Flat buffer memory
- Flat buffers in use
- Private buffer memory
- Private buffers in use
- Rows read
- Rows written
Q65. What is Analysis Services? List out the features?
Ans: Microsoft SQL Server 2014 Analysis Services (SSAS) delivers online analytical processing (OLAP) and data mining functionality for business intelligence applications. Analysis Services supports OLAP by letting us design, create, and manage multidimensional structures that contain data aggregated from other data sources, such as relational databases. For data mining applications, Analysis Services lets we design, create, and visualize data mining models that are constructed from other data sources by using a wide variety of industry-standard data mining algorithms.
Analysis Services is a middle tier server for analytical processing, OLAP, and Data mining. It manages multidimensional cubes of data and provides access to heaps of information including aggregation of data. One can create data mining models from data sources and use it for Business Intelligence also including reporting features.
Analysis service provides a combined view of the data used in OLAP or Data mining. Services here refer to OLAP, Data mining. Analysis services assists in creating, designing and managing multidimensional structures containing data from varied sources. It provides a wide array of data mining algorithms for specific trends and needs.
Some of the key features are:
- Ease of use with a lot of wizards and designers.
- Flexible data model creation and management
- Scalable architecture to handle OLAP
- Provides integration of administration tools, data sources, security, caching, and reporting etc.
- Provides extensive support for custom applications
Q66. What is UDM? Its significance in SSAS?
Ans: The role of a Unified Dimensional Model (UDM) is to provide a bridge between the user and the data sources. A UDM is constructed over one or more physical data sources, and then the end user issues queries against the UDM using one of a variety of client tools, such as Microsoft Excel. At a minimum, when the UDM is constructed merely as a thin layer over the data source, the advantages to the end user are a simpler, more readily understood model of the data, isolation from heterogeneous backend data sources, and improved performance for summary type queries. In some scenarios a simple UDM like this is constructed totally automatically. With greater investment in the construction of the UDM, additional benefits accrue from the richness of metadata that the model can provide.
The UDM provides the following benefits:
• Allows the user model to be greatly enriched.
• Provides high performance queries supporting interactive analysis, even over huge data volumes.
• Allows business rules to be captured in the model to support richer analysis.
Q67. What is the need for SSAS component?
Ans:
- Analysis Services is the only component in SQL Server using which we can perform Analysis and Forecast operations.
- SSAS is very easy to use and interactive.
- Faster Analysis and Troubleshooting.
- Ability to create and manage Data warehouses.
- Apply efficient Security Principles.
Q68. Explain the TWO-Tier Architecture of SSAS?
Ans:
- SSAS uses both server and client components to supply OLAP and data mining functionality BI Applications.
- The server component is implemented as a Microsoft Windows service. Each instance of Analysis Services implemented as a separate instance of the Windows service.
- Clients communicate with Analysis Services using the standard XMLA (XML For Analysis) , protocol for issuing commands and receiving responses, exposed as a web service.
Q69. What are the components of SSAS?
Ans:
- An OLAP Engine is used for enabling fast adhoc queries by end users. A user can interactively explore data by drilling, slicing or pivoting.
- Drilling refers to the process of exploring details of the data.
- Slicing refers to the process of placing data in rows and columns.
- Pivoting refers to switching categories of data between rows and columns.
- In OLAP, we will be using what are called as Dimensional Databases.
Q70. What is FASMI ?
Ans:
A database is called an OLAP Database if the database satisfies the FASMI rules :
- Fast Analysis– is defined in the OLAP scenario in five seconds or less.
- Shared – Must support access to data by many users in the factors of Sensitivity and Write Backs.
- Multidimensional – The data inside the OLAP Database must be multidimensional in structure.
- Information – The OLAP database Must support large volumes of data..
Q71. What languages are used in SSAS ?
Ans:
- Structured Query Language (SQL)
- Multidimensional Expressions (MDX) - an industry standard query language orientated towards analysis
- Data Mining Extensions (DMX) - an industry standard query language oriented toward data mining.
- Analysis Services Scripting Language (ASSL) - used to manage Analysis Services database objects.
Q72. How Cubes are implemented in SSAS ?
Ans:
- Cubes are multidimensional models that store data from one or more sources.
- Cubes can also store aggregations
- SSAS Cubes are created using the Cube Wizard.
- We also build Dimensions when creating Cubes.
- Cubes can see only the DSV( logical View).
Q73. What is the difference between a derived measure and a calculated measure?
Ans: The difference between a derived measure and a calculated measure is when the calculation is performed. A derived measure is calculated before aggregations are created, and the values of the derived measure are stored in the cube. A calculated measure is calculated after aggregations are created, and the values of a calculated measure aren’t stored in the cube. The primary criterion for choosing between a derived measure and a calculated measure is not efficiency, but accuracy.
Q74. What is a partition?
Ans: A partition in Analysis Services is the physical location of stored cube data. Every cube has at least one partition by default. Each time we create a measure group, another partition is created. Queries run faster against a partitioned cube because Analysis Services only needs to read data from the partitions that contain the answers to the queries. Queries run even faster when partition also stores aggregations, the pre calculated totals for additive measures. Partitions are a powerful and flexible means of managing cubes, especially large cubes.
Q75. While creating a new calculated member in a cube what is the use of property
called non-empty behavior?
Ans: Nonempty behavior is important property for ratio calculations. If the denominator Is empty, an MDX expression will return an error just as it would if the denominator Were equal to zero. By selecting one or more measures for the Non-Empty Behavior property, we are establishing a requirement that each selected measure first be evaluated before the calculation expression is evaluated. If each selected measure is empty, then The expression is also treated as empty and no error is returned.
Q76. What is a RAGGED hierarchy?
Ans: Under normal circumstances, each level in a hierarchy in Microsoft SQL Server Analysis Services (SSAS) has the same number of members above it as any other member at the same level. In a ragged hierarchy, the logical parent member of at least one member is not in the level immediately above the member. When this occurs, the hierarchy descends to different levels for different drilldown paths. Expanding through every level for every drilldown path is then unnecessarily complicated.
Q77. What are the roles of an Analysis Services Information Worker?
Ans: The role of an Analysis Services information worker is the traditional "domain expert" role in business intelligence (BI) someone who understands the data employed by a solution and is able to translate the data into business information. The role of an Analysis Services information worker often has one of the following job titles: Business Analyst (Report Consumer), Manager (Report Consumer), Technical Trainer, Help Desk/Operation, or Network Administrator.
Q78. What are the different ways of creating Aggregations?
Ans: We can create aggregations for faster MDX statements using Aggregation Wizard or thru UBO – Usage Based Optimizations. Always, prefer UBO method in realtime performance troubleshooting.
Q79. What is WriteBack? What are the pre-conditions?
Ans: The Enable/Disable Writeback dialog box enables or disables writeback for a measure group in a cube. Enabling wri
teback on a measure group defines a writeback partition and creates a writeback table for that measure group. Disabling writeback on a measure group removes the writeback partition but does not delete the writeback table, to avoid unanticipated data loss.
Q80. What is processing?
Ans: Processing is a critical and resource intensive operation in the data warehouse lifecycle and needs to be carefully optimized and executed. Analysis Services offers a high performance and scalable processing architecture with a comprehensive set of controls for database administrators.
We can process an OLAP database, individual cube, Dimension or a specific Partition in a cube.
Q81. Name few Business Analysis Enhancements for SSAS?
Ans: The following table lists the business intelligence enhancements that are available in Microsoft SQL Server Analysis Services (SSAS). The table also shows the cube or dimension to which each business intelligence enhancement applies, and indicates whether an enhancement can be applied to an object that was created without using a data source and for which no schema has been generated.
Enhancement | Type | Applied to | No data source |
Time Intelligence | Cube | Cube | No |
Account Intelligence | Dimension | Dimension or cube | No |
Dimension Intelligence | Dimension | Dimension or cube | Yes |
Custom Aggregation | Dimension | Dimension (unary operator) or cube | No |
Semiadditive Behavior | Cube | Cube | Yes |
Custom Member Formula | Dimension | Dimension or cube | No |
Custom Sorting and Uniqueness Settings | Dimension | Dimension or cube | Yes |
Dimension Writeback | Dimension | Dimension or cube | Yes |
Q82. What MDX functions do you most commonly use?
Ans: This is a great question because you only know this answer by experience. If you ask me this question, the answer practically rushes out of me. “CrossJoin, Descendants, and NonEmpty, in addition to Sum, Count, and Aggregate. My personal favorite is CrossJoin because it allows me identify non-contiguous slices of the cube and aggregate even though those cube cells don’t roll up to a natural ancestor.” Indeed, CrossJoin has easily been my bread and butter.
Q83. Where do you put calculated members?
Ans: The reflexive answer is “in the Measures dimension” but this is the obvious answer. So I always follow up with another question. “If you want to create a calculated member that intersects all measures, where do you put it?” A high percentage of candidates can’t answer this question, and the answer is “In a dimension other than Measures.” If they can answer it, I immediately ask them why. The answer is “Because a member in a dimension cannot intersect its own relatives in that dimension.”