Following are frequently asked SSIS Interview questions for freshers as well as experienced Database managers.
1) What is SSIS?
SSIS or SQL Server Integration Services (SSIS) is a component of Microsoft SQL Server, which can be used to accomplish a broad range of data transformation and migration tasks.
2) What are the important components of SSIS package?
The important component in SSIS package are
- Data flow
- Control flow
- Package Explorer
- Event handler
3) Explain solution Explorer in SSIS
Solution Explorer in SSIS Designer is a screen where you can view and access all the data sources, data sources views, projects, and other miscellaneous files.
4) What does it mean by data flow in SSIS?
Data flow in SSIS is nothing but the flow of data from the corresponding sources to the target destinations.
5) Define what is "task" in SSIS?
A task in SSIS is very much similar to the method of any programming language that represents or carries out an individual unit of work. Tasks are categorized into two categories
- Control Flow Tasks
- Database Maintenance Tasks
6) What is an SSIS package?
A package in SSIS is an organized collection of connections like data flow elements, control events, event handlers, parameters, variables, and configurations. You assemble them either building it programmatically or by graphical design tools that SSIS provides.
7) Name different types of connection or files that support SSIS?
Different types of connection that work within SSIS are
- .net SQLClient
- Flat File
8) What is a container? How many types of containers are there in SSIS?
In SSIS, a container is a logical grouping of tasks, and it allows to manage the scope of a task together. Types of containers in SSIS are
- Sequence container
- For loop container
- Foreach loop container
- Task host container
9) What is Precedence Constraint in SSIS?
Precedence Constraint in SSIS enables you to define the logical sequence of tasks in the order they should be executed. You can connect all the tasks using connectors- Precedence Constraints.
10) What variables in SSIS and what are the types of variables in SSIS?
Variable in SSIS is used to store values. In SSIS, there are two types of variables system variable and user variable.
11) Explain what Ws a checkpoint in SSIS?
Checkpoint in SSIS allows the project to restart from the point of failure. Checkpoint file stores the information about the package execution, if the package run successfully the checkpoint file is deleted or else it will restart from the point of failure.
12) Explain connection managers in SSIS
While gathering data from different sources and writing it to a destination, connection managers are helpful. Connection manager facilitates the connection to the system that includes information's like data provider information, server name, authentication mechanism, database name, etc.
13) What is SSIS breakpoint?
A breakpoint enables you to pause the execution of the package in the business intelligence development studio during troubleshooting or development of an SSIS package.
14) Explain event logging in SSIS
In SSIS, event logging allows you to select any specific event of a task or a package to be logged. It is beneficial when you are troubleshooting your package to understand the performance package.
15) What is logging mode property?
SSIS packages and all the associated tasks have a property called LoggingMode. This property accepts three possible values.
- Disabled: To disable logging of the component
- Enabled: To enable logging of the part
- Use Parent Setting: To use the parent's setting of the component
16) Explain the term data flow buffer?
SSIS operates using buffers; it is a kind of an in-memory virtual table to hold data.
17) For what data checkpoint data is not saved?
Checkpoint data is not saved for For Each Loop and For Loop containers.
18) What is conditional split transactions in SSIS?
Conditional split transformation in SSIS is just like IF condition, which checks for the given condition based on the condition evaluation.
19) Name different types of Data viewers in SSIS?
Different types of data viewers in SSIS include
- Scatter Plot
- Column Chart
20) Explain the possible locations to save the SSIS package?
You can save SSIS package at
- SQL Server
- Package Store
- File System
21) What will be your first approach if the package that runs fine in Business Intelligence Development Studio (BIDS) but fails when running from an SQL agent job?
The account that runs SQL Agent Jobs might not have the required permission for one of the connections in your package. In such cases, either you can create a proxy account or elevate the account permissions.
22) What is the role of the Event Handlers tab in SSIS?
On the event handlers tab, workflows can be configured to respond to package events. For instance, you can configure workflow when any task stops, fails or starts.
23) How you can notify the staff members about package failure?
Either inside the package, you could add a Send Mail Task in the event handlers, or you can even set the notification in the SQL Agent when the package runs.
24) How would you do logging in SSIS?
Logging in SSIS can be done by logging various events like onError, onWarning, etc. to the multiple options like a flat file, XML, SQL server table, etc.
25) How would you deploy an SSIS package on production?
To deploy SSIS package we need to execute the manifest files and need to determine whether to deploy this into File System or onto SQL Server. Alternatively, you can also import package from SSMS from SQL Server or File System.
26) How to handle Early Arriving Facts or Late Arriving Dimension?
Late Arriving Dimension are unavoidable; to handle these we can create a dummy dimension with natural/business key and keep the rest of the attributes as null or default. So when the actual dimension arrives, the dummy dimension is updated with Type 1 change. This is also referred to as Inferred Dimensions.
27) Explain the method to perform incremental load?
The best and fastest way to do incremental load is by using Timestamp column in the source table and storing the last ETL timestamp.
28) Name three data flow components in SSIS
Three data flow components is SSIS are:
29) Why check Points used in SSIS?
Checkpoint used in SSIS to allows a package to restart at the point of failure.
30) Explain event logging mode property
The three values accept by event logging mode property are:
- Enabled: Allows you to logging of the components
- Disabled: It is used to disable the components
- UserParentSetting: It is used to optimize the parent’s setting.
31) Explain different options for dynamic configuration is SSIS.
Different option for dynamic configuration are:
- XML file
- Customer variables
- Database per environment with the variables
- Allows you to use a centralized database with all variables
32) Explain Data conversion Transformation
Data conversion is the best method to convey the data from one type to another. However, you need to make sure that you have COMPATIBLE data in the column.
33) Explain few features of SSIS
Some important features of SSIS are:
- Studio Environments
- Relevant data analytics and integration functions
- Tight integration with other Microsoft SQL family
- Data Mining Query Transformation
34) Explain two disadvantages of SSIS
- SIS sometimes create issues in non-windows environments
- Unclear vision and strategy
- SSIS doesn't provide support for alternative data integration styles
35) What is the use of Execute SQL task in SSIS?
Execute SQL helps you to execute a SQL statement against a relational database.
36) What is an SSIS Catalog?
The SSIS catalog is a database to store all the deployed packages. It is widely used for security reasons to store and handle the deployed packages.
37) How would you stop a package that is running forever?
It depends. If you are running the package in the SQL Agent, you can kill the process using T-SQL. However, if the package is running in the SSIS catalog, you can stop it using Active Operations window or the stop operation stored procedure.
38) Explain project and package control flow in SSIS
In SSIS, a project is a container for developing package while the package is an object which helps you to implement ETL.
39) Explain use of XML Task
XML task allows you to split, merge, split or reformat any XML file.
40) What is the use of a sequence container?
Sequence contain helps you to organize subsidiary tasks by dividing them into the group. It will enable you to apply transaction or assign logging to the container.
41) What are important best practices for using SSIS?
The best practices for using the SISS tool are:
- You should avoid performing logged operations
- You should make a clear plan for resource utilization.
- Optimize the data source, lookup transformation, and destination
42) What is the use of control flow tab in SSIS?
Control flow tab in SSIS includes dataflow task, containers and precedence constraints which helps you to connect containers and functions.