The theory discussed in this Post is the theory what told to me by my CS friend in short.So ,it is not verified ....it is suggested that kindly take it as an overview and rest study from some standard books related to DBMS
--DBMS is the work of back end work (of a website or some software) where as frontend is about GUI and linking links.
--Core skill which will be used in industry are mainly SQL commands
--map out the meaning of Entity ,Attribute and value of a Table before learning SQL
--When comparing data of one table with another than we do normalisation
--Normalisation are of 3 Types
--1NF (when comparing two tables )
--2NF (when comparing three tables let say A,B,C and A is related to B is related to C but A is not related to C)
--3NF(when comparing three tables let say A,B,C and A is related to B is related to C and this time also A is related to C)
--Primary Key
the key of your first table/reference table or which you considered first which may be common in another upcoming tables too like your name then name would be primary key and the same key would be foreign key in another table.
This Post will be updated once i study from some standard books.
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