Data modelling is the process of developing data models for data before being stored in a data warehouse. It involves visualisation & representation of data before storing it in the data warehouse. Data modeling ensures a persistent way of data source management within an organisation.
In its simplest form, data transformation can be defined as transforming data from one format to another, typically from the format of a source system into the required format of a destination system. The most common data transformations are converting raw data into a clean and usable form. Raw data often contains inconsistent and imprecise data. that needs to be restructured. In this step, you may add or copy data, delete certain fields, standardise records, or rename and restructure the data.
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