Er Diagram to Table 1

Question

The number of minimum Relations which satisfy 1NF _________. (Partial participation between E₁ and R should not lost in RDBMS design).

Please explain every point in detail i am weak in ER Diagram to table conversion Please

Comments

Why not just 1 table, 1nf doesn't care about redundancy . So we can have 1 table with primary key (A D).

And how having one table loses partial participation(oppose to the answer given by made easy). As its not given that there is entity integrity constraint in play.

Sometimes they ignore entity integrity and here they're taking it into effect.

Answer 1

Relation means Table. Three tables will be formed: two for entities and one for M:N relationship. 

1NF requires attributes to be atomic.

Relation is a set of tuples and that's why it can't have duplicate tuples/rows because sets don't allow duplicates. Thus, all relations are in 1NF because each tuple of a relation is unique.

This means all the three tables are in 1NF.

But if we go into language implementation, like SQL, then the answer would be language specific. For example, in SQL we would have 0 as answer because duplicate tuples are allowed in SQL. Go through this:

https://stackoverflow.com/questions/30767562/why-does-sql-standard-allow-duplicate-rows

Comments

Ohk sir in this question : https://gateoverflow.in/3717/gate2004-it-73

Arjun sir said that for 1nf two table is enough because sir, did the same thing as the above i.e. breaking the multivalued attribute two different column. Hence 1nf is satisfied but not 2nf because doing this satisfied 1nf but created a partial dependency therefore we needed to draw a separate table isn't it Sir?

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Sir in techopedia link for 1nf plz explain following points :

• Separate tables must be created for each set of related data
• no row/column intersections contain a null value.

And sir if we can remove multivalued attribute like they have shown and composite attribute can be removed by adding extra attribute then every relation can be brought into 1nf by using only 1 table is it Sir? 

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@akhilesh singla Beacuse of total participation no record will be left to map but also given relation in 1nf so redundancy is allowed ,so we can merge relation R to E2

For merging two condition should be there ,

(1) participation should be preserve

(2) redudancy should not be there

If in above question total is not given then there will be three table no one can merge but total participation and 1nf is given ,so R can merge with E2