Introduction to SSIS
SQL Server Integration Services or better abbreviated as SSIS is a tool that is used to perform database related operations like Extract, Transform and Load data. Extraction, loading, and transformation of data involve tasks like cleaning, merging, and aggregation of data. It is a flexible and smooth tool, which is a component of SQL Server Database. It is widely used and one of the most popular tools for performing ETL operations. SSIS offers a very wide range of options like the ability to extract data from sources like JSON, Excel Files, Databases (Oracle, SQL Server), sending data over FTP, IP and emails.
Why do we need SSIS with the Usage
SQL Server Integration services, as the name suggests, provides a whole bunch of services for the SQL Server Database. The extraction of data from any kind of source is made possible using SSIS. SSIS has the ability to extract data from sources like JSON, Excel Files, CSV files, XML files, and other databases like Oracle DB. Apart from extraction, the data from different sources can be merged using this tool. The above two functions contribute to the property where the developer is able to organize, clean up and systemize the data before loading it to any database using SSIS.
SQL Server Integration Services is a graphical user interface with a huge option set, where users can build automated solutions without heavy coding. Drag and drop different task boxes into the workflow and run the flow to generate results. Besides offering developers a platform for easy solutions, SSIS has speed as another of its advantage. A huge data set can be loaded from one source to another within a matter of a few seconds or minutes. The elimination of coding lets the developer get rid of many other coding aspects like maintenance of IDE plugins, upgradation of code, coding best practices, etc. There is freedom of creating an automated flow using various components available in the toolbox.
It’s a good tool, one of the best in current times, being used for the population of data warehouses, given that, this platform automates the process of data loading, extraction, and transformation. The ease of use and various features being offered for analysis, identification, and processing of data is what drives the developer to use SSIS.
Working Of SSIS
SQL Server Integrated Services is a platform that comprises five major components namely, Control Flow, Data Flow, Tasks, Package, Parameters. Here, control flow can be called the powerhouse of SSIS. Control flow is where the developer arranges the steps of automation i.e. various tasks that need to take place for a job to get done. Control Flow is where the order of execution is also decided. The tasks/components can be dragged and dropped in a flow-like structure, according to the order in which they need to take place.
The next major component in SSIS is Data Flow. As the name suggests, Data Flow is the part where all the data related operations happen. This is where data can be extracted from any source (JSON, XML, Excel, DB tables, etc). If there needs to be any transformation applied to this data, as the addition of text or modification of the extracted dates or any kind of filter, that also happens in the data flow. Finally, the data flow is where the destination for loading the data is defined. The entire ETL happens within the data flow and once this is completed successfully, the control moves back to the control flow to the next task/container lined up after the data flow.
The next component of the SSIS tool is a Task. It is a unit of work or set of instructions. The only difference here is that it’s a drag and drop option which can be configured and modified once called in the control flow. Data Flow is an SSIS task. Some other tasks are namely Execute SQL Task (for executing a SQL Query directly from control flow), File System Task (reading, writing, manipulation of a file), Send Mail Task (sending out emails), FTP task (establish a connection to a destination using FTP to extract or load data), XML Task, etc. These tasks can be grouped as well. A group of tasks is known as a container. The container can work in three ways which are Sequence Container (a set of tasks arranged in order and can be modified together), For Loop Container (a set of tasks, which run in a loop till when a given condition is true), and For Each Loop Container.
Another component of SSIS is the Package which is also called SSIS Package. The complete control flow, which is a set of tasks arranged in order along with president constraints is called a Package. President constraints are nothing but minimal conditions fulfilled by a task before moving on to the next task. Control flow combined with Data flows constitute a package. This package is saved and deployed. And when a job is scheduled for this package, that means that these steps (tasks) will run to fulfill the objective of the flow defined in the package.
Lastly, there are parameters, which can be looked at as variables. These are values needed in the package for various tasks to be completed. They can be hardcoded or provided at run-time by the user.
Advantages of SSIS
Some of the major benefits of SQL Server Integration Services are:
- No requirement for coding. The drag and drop technique is used for the creation of workflows
- Minimal maintenance needed. The packages are automated and run on the scheduled job
- SQL Server and Visual Studio are tightly integrated through this platform
- Implementation is not time taken and flows are speedy.
Disadvantages of SSIS
- Heavily dependent on SQL Server. The packages can fail if the database is down.
- Integration with third-party services is flaky.
This article covered SSIS very briefly. If someone is willing to take up development using SSIS, they must make sure they have a strong knowledge of SQL Server Database and a basic understanding of automation.
This is a guide to SSIS. Here we discuss Why do we need SSIS with the Usage along with the working, advantages, and disadvantages. You may also have a look at the following articles to learn more –