DWH Tutorial - 2

What are virtual cubes? These are combinations of one or more real cubes and require no disk space to store them. They store only the definitions and not the data of the referenced source cubes. They are similar to views in relational databases. What are MOLAP cubes? MOLAP Cubes:   stands for Multidimensional OLAP. In MOLAP cubes the data aggregations and a copy of the fact data are stored in a multidimensional structure on the Analysis Server computer. It is best when extra storage space is available on the Analysis Server computer and the best query performance is desired. MOLAP local cubes contain all the necessary...

DWH Tutorial - 1

What is OLTP? OLTP stands for Online Transaction Processing. OLTP uses normalized tables to quickly record large amounts of transactions while making sure that these updates of data occur in as few places as possible. Consequently OLTP database are designed for recording the daily operations and transactions of a business. E.g. a timecard system that supports a large production environment must record successfully a large number of updates during critical periods like lunch hour, breaks, startup and close of work. What are dimensions? Dimensions are categories by which summarized data can be viewed. E.g. a profit summary...

DWH Tutorials

What is a data warehouse? A data warehouse is a collection of data marts representing historical data from different operations in the company. This data is stored in a structure optimized for querying and data analysis as a data warehouse. Table design, dimensions and organization should be consistent throughout a data warehouse so that reports or queries across the data warehouse are consistent. A data warehouse can also be viewed as a database for historical data from different functions within a company. What is a data mart? A data mart is a segment of a data warehouse that can provide data for reporting and analysis...

Learning’s Informatica Power Center

1.       Assigning the workflow variables value to the mapping variable in a session (in component tab ->pre-session variable assignment info8.6) is not possible in the reusable session. It will not assign value if it is a reusable session. If you want to assign the value like that go for normal session. i.e session created in workflow directly. 2.       If the parameter is a string no need to give the value in the single quote in the parameter file. Even in the mapping also no need to give single quotes for the parameter. 3.      ...