Informatica Interview Questions & Answers: A. What are the differences between Connected and Unconnected lookup? Connected lookup participates in the mapping(dataflow), just like any other transformation. Unconnected lookup is used when a lookup function is used instead in an expression transformation in the mapping in which case the lookup does not appear in the main…
System Testing: This environment integrates the various components and runs as a single unit. This should include sequences of events that enable those different components to run as a single unit and validate the data flow. Verify all the required functionality in the validation environment. Run end-to-end system test. Record initialization and incremental load statistics….
Test Estimation: Effective software project estimation is one of the most challenging and important activities in the testing activities. However, it is the most essential part of a proper project planning and control. Under-estimating a project leads to under-staffing it, running the risk of low quality deliverables and resulting in loss of credibility as deadlines…
ETL Testing: Testing is an important phase in the project life-cycle. A structured well defined testing methodology involving comprehensive unit testing and system testing not only ensures smooth transition to the production environment but also a system without defects. The testing phase can be broadly classified into the following categories: Integration Testing System Testing Regression…
Data Warehouse & ETL Tutorial: Data Warehouse is where data from different source systems are integrated, processed and stored. Data Warehouse data is a non-production data which is mainly used for analyzing and reporting purposes. Business users and higher management authorities use the data warehouse data to analyze, and to make important business decisions. Data…
ETL Concepts: Extraction, transformation, and loading. ETL refers to the methods involved in accessing and manipulating source data and loading it into target database. The first step in ETL process is mapping the data between source systems and target database(data warehouse or data mart). The second step is cleansing of source data in staging area….
ETL Tools: What to Learn? With the help of ETL tools, we can create powerful target Data Warehouses without much difficulty. Following are the various options that we have to know and learn in order to use ETL tools. Software: How to install ETL tool on server/client? Working with an ETL Tool: How to work…
What are ETL Tools? ETL Tools are meant to extract, transform and load the data into Data Warehouse for decision making. Before the evolution of ETL Tools, the above mentioned ETL process was done manually by using SQL code created by programmers. This task was tedious and cumbersome in many cases since it involved many…
Database – RDBMS: There are a number of relational databases to store data. A relational database contains normalized data stored in tables. Tables contain records and columns. RDBMS makes it easy to work with individual records. Each row contains a unique instance of data for the categories defined by the columns. RDBMS are used in…
What is a Data Warehouse? According to Inmon, famous author for several data warehouse books, “A data warehouse is a subject oriented, integrated, time variant, non volatile collection of data in support of management’s decision making process”. In order to store data, over the years, many application designers in each branch have made their individual decisions…
