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ETL Testing Services

Outsource ETL Testing Services

Get access to high-quality ETL testing services provided by expert software testers at prices starting from only $20/hour

ETL - Extract/Transform/Load - is a process that extracts data from a source system, transforms it into a consistent data type, and then loads the data into a single data repository. ETL testing is performed to ensure that any data that has been loaded from a source-destination after transformation to a new destination is accurate. It involves verifying the data at various stages between the source and destination. Data is usually extracted from the OLTP database, transformed into the required form to match the schema and finally loaded into the data warehouse database. ETL testing is ideal for companies dealing majorly with historical data such as financial, travel, etc.

When implementing an Extract, Transform, and Load (ETL) system for business intelligence, the major risk lies in rushing a data warehouse into service without testing it thoroughly.

Outsource2india's ETL testing process ensures that all your systems and data are tested systematically for bugs, errors, and vulnerabilities before the data is integrated and made available.

Our ETL Testing Services

Our highly talented team of software testers is well trained to work on different technologies and testing environments. Some of the key ETL testing services we provide include -

  1. Source to Target Testing

    Source to Target Testing

    This type of testing is carried out to check whether the data values which have been transformed are the expected data values or not. This ensures data compatibility and prevents any risk of data loss.

  2. Production Validation Testing

    Production Validation Testing

    This testing is done on data when it is being moved to the production systems. The data in the production system must be in the correct order without which the whole process of transfer would become useless. Our services ensure that the data does not compromise the production systems' integrity.

  3. Testing for Application Upgrades

    Testing for Application Upgrades

    We are a top ETL testing services company, and under this service, we check if the data extracted from the older repository or application is the same as the data present in the new application. These can be automatically generated hence saving considerable development time for your data warehouse developers.

  4. Metadata Testing

    Metadata Testing

    A metadata repository containing all information about the source, target, mappings, transformations, etc. is extremely important in ETL. As a top ETL testing service provider, Outsource2india's metadata testing involves data length checks, testing data types, and index/constraint checks, allowing you to maintain a steady control over your organization's overall information systems.

  5. Data Completeness Testing

    Data Completeness Testing

    As a top provider of ETL testing services in India and abroad, we provide comprehensive data completeness testing. This testing aggregates actual data between the source and the target for columns with simple transformation or no transformation. This is done to check if all the expected data is loaded on to the target from the source in the correct manner.

  6. Data Accuracy Testing

    Data Accuracy Testing

    This is a type of testing that ensures that the data is loaded correctly and transformed as expected. Our testers are experts at testing the accuracy and completeness of your data and follow time-tested procedures in order to ensure complete data integrity.

  7. Data Transformation Testing

    Data Transformation Testing

    In many cases, data transformation cannot be done by writing just one SQL query and comparing the output with the target. In our transformation testing process, multiple SQL queries are written to run each row and verify the transformational rules.

  8. Data Quality Testing

    Data Quality Testing

    We provide data quality tests which include syntax and reference tests. This is done to avoid any kind of error caused due to different scenarios such as incorrect order numbers or dates during the business process.

  9. GUI/Navigation Testing

    GUI/Navigation Testing

    We provide GUI/navigation testing support to check if the GUI aspects or navigation of the front end are functioning properly and generate an exhaustive report for the same.

  10. Incremental ETL Testing

    Incremental ETL Testing

    We provide incremental ETL testing services to check the data integrity of new and old data with the addition of the new data. It also verifies that the updates and inserts are being processed as expected during the incremental ETL process.

Types of ETL Bugs

The following table lists some of the common ETL Bugs -

Types of ETL Bugs
Types of ETL Bugs
User Interface Bugs
These are associated with the GUI of application and have to do with things like color, font style, and navigation.
Types of ETL Bugs
Input-Output Bugs
Here, the application begins taking invalid values while rejecting valid ones.
Types of ETL Bugs
Boundary Value Analysis Bugs
In these types of bugs, the minimum and maximum values are checked.
Types of ETL Bugs
Calculation Bugs
Here, mathematical errors appear and, in most cases, the final output is wrong.
Types of ETL Bugs
Load Condition Bugs
These bugs prevent multiple users from using the app. They also do not -allow the data that is user-accepted.
Types of ETL Bugs
Race Condition Bugs
With these bugs, the system will be unstable and hang or crash.
Types of ETL Bugs
Equivalence Class Partitioning Bugs
These types of bugs throw out invalid results or types.
Types of ETL Bugs
Version Control Bugs
These usually occur during regression testing.
Types of ETL Bugs
Hardware Bugs
Here, the device does not respond as expected.
Types of ETL Bugs
Help Source Bugs
With these types of bugs, there will be errors in the help documents.

Challenges Faced During ETL Testing

There are many challenges faced during ETL testing, some of which are -

 The presence of incompatible and duplicate data
 Data loss during the ETL process
 Data volume and complexity being very large
 Business flow information not being available

Benefits of ETL Testing

There are many benefits to performing ETL testing. ETL testing can -

 Extract or recover data from multiple data sources at the same time.
 Load the data from heterogeneous sources into a single generalized (frequent) target or different targets at the same time.
 Load different types of goals at the same time.
 Extract the required business data from multiple sources and load business data into different targets in the desired format.
 Perform any type of data transformation as per business requirements.

Outsource2india's ETL Testing Process

As a top ETL testing service providing company, Outsource2india provides high-quality ETL testing services, including data warehouse testing services and data validation in ETL testing, to global clients according to their business needs. We follow a 5-step streamlined and systematic ETL testing process in order to provide world-class services to our clients: Key steps are -


01. Requirement Gathering

In this step, we design the data model, define the business flow, and evaluate the reporting needs as per your expectations. This is important so that the testers fully understand the scope of the project.


02. Data Source Validation

In this step, we perform a check of the data count and make sure that the table and column data type is according to the specifications of the data model. We ensure that check keys are in place and delete any duplicate data. We pay high attention to detail in this step since we know that errors can lead to inaccuracies in the aggregate report.


03. Test Case Designing

Here, we define and design ETL mapping scenarios and create SQL scripts. We also define transformational rules. In addition, we validate the mapping document to ensure that it contains all of the information.


04. Source System Data Extraction

In this step, we execute ETL tests. We identify the types of bugs or errors found during testing and create a report. This step is important because every defect needs to be detected and reproduced, reported on, fixed, resolved, and the bug report closed before proceeding to the next step.


05. Transformation Logic Application

We make sure that all the data is transformed to match the schema of the target data repository. We check the data threshold, data alignment, and validate the data flow. This step is necessary to ensure that the data type correctly matches the mapping document for every column and table.


06. Loading of Data into Target Warehouse

Here, we perform a check of the record count both before and after the data is moved from the staging area to the data warehouse. We make sure to check that all the invalid data is rejected and that the correct default values are accepted.


07. Summary Report Creation

We verify and finalize things like the layout, filters, options and export functionality of the summary report. This report provides stakeholders with the details of the testing process and lets them know things like why any step might have not been done.


08. Closure of Test

In this step, we perform the final file test closure.

Why Choose Outsource2india for ETL Testing Services?

Outsource2india has been providing high-quality ETL testing services to clients around the world for 25 years. Outsourcing ETL testing services to us comes with its own set of benefits, including -

  • Cost-effective Prices

    We provide the best quality ETL software testing services at competitive prices within quick turnaround time.

  • Quality

    Our testing engineers can assure complete adherence to new and strict quality standards and increase your testing coverage.

  • Testing Team

    Our ETL testing team has 25 years of experience in providing high-quality ETL testing services.

  • Tools and Technologies

    Our team of highly experienced software testers is trained to work with the latest ETL testing tools and technologies and is updated with the best practices.

  • Independent Validation

    We provide independent verification and validation of your ETL process if required.

  • Immediate Access to Test Documentation

    Your developers receive immediate access to the test documentation to study the results of the test and gain a better understanding of it.

  • Efficiency

    We help you organize large repositories of data in an efficient manner.

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Hire the Best ETL Testers at Outsource2india


I want to thank you for all the superb services your team has provided. You have been a pleasure to work with and have also been professional and timely.

Video Marketing company in Chicago
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Outsource2india has been providing ETL testing and software testing services to global clients for 25 years. Our experience in working with several clients has provided us with the ability to understand different business models and provide the required ETL testing services customized as per their needs and requirements. The applications tested by us are known to run smoothly without any errors and provide high performance and efficiency gains.

If you have any kind of ETL testing service requirement, feel free to get in touch with us or talk to one of our representatives and we will get back to you within 24 hours.

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