What is the difference between data design and data model(ERD) -

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i have google question , find answer in day. know, data design many many table have list column,and mark pk , fk. why er-diagram have find this?

data design process of designing database. main output of data design detailed logical data model of database.

some people data design includes of needed logical , physical design choices , physical storage parameters needed generate design in data definition language. technically, database analysis, database analysts (dbas) trained do.

while person can both data design , database analysis, these 2 different tasks. data design models data. database analysis takes model , applies 1 or more database engines (relational, hierarchical, nosql).

a logical data model 1 of main outputs of data design. data model represented entity relationship diagram, or er diagram.


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