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Title: Data Model Vs Data Mapping Post by: Sowjanya on May 26, 2008, 11:44:22 am Hi
Can anyone tell me the difference between 1) Data Model and Data mapping? 2) LDM and HDM Thanks Sowjanya Title: Re: Data Model Vs Data Mapping Post by: Sowjanya on June 04, 2008, 10:09:43 am hi
Finally i am replying to my own post >:( 1) Datamodel Vs Datamapping LDM and PDM means Logical Data Model and Physical Datamodel. LDM is at the manager and above level which contains the detailed pictures of the tables, their columns (Ex Emplyee Identification Number) and how they are connected to each other.PDM is at the lower level which contains the tables and their columns in a short form(ex:Emp_Id),their datatypes and not null/null condition. Both of them are pertaining to the database. 2) Data mapping can be explained with the following example: For Ex: Say we have two tables. Department with columns Dept_Id,Dept_Name and Employee with columns Emp_Id,Emp_Name and Dept_Id. This is pertaining to ETL not reporting. From source, when we are loading these to the target, which column is matching to what is called data mapping. First,Department table has to be feeded, then employee table. So, the source needs to map with the Dept_ID column in the Department table and the same Dept_ID should be mapped to the one in the employee table. Because both of them should be same. Hope i am clear. In case of any questions, please shoot them unhesistantly. Thanks & Regards Sowjanya Title: Re: Data Model Vs Data Mapping Post by: Arvind on July 15, 2008, 09:56:39 pm Quote Finally i am replying to my own post Sowjanya - Don't get disappointed. :( All experts are not guru's :o. Have patience and your question is also known to all buddies.... :-\ |