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Number of tables required in above ER diagram will be _____________


Is $R_{1}$ create separate table or not?? and $R_{2}$ look like if we remove loop from it??

Answer given for table $E_{1}R_{1}$ Key will be $AC$ , with $C$ foreign key.

And for $E_{2}R_{2}$ Key will be $C$ and $C_{1}$ foreign key.

But I think $E_{2}$ itself $2$ Entities. So, it will add one extra table.

I already read https://gateoverflow.in/229580/madeeasy-test-series-number-of-tables-required

in Databases by Veteran (116k points) | 84 views
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@srestha
what does that arrow from R1 to E2 indicates?
I know arrow from entity to relationship indicates 0 or 1 participation

0
yes, arrow means m:1 partial participation
0

@srestha

here the arrow is from relationship to entity

arrow from entity to relationship means m:1

0
where u got that?

arrow always from relationship to entity side and it is in $1$ side

nothing more :
0
then why is there arrow from entity E2 to relationship R2?
0
that is the tricky part of this ques, If we find it out correctly, question will be done.

We havenot seen such a symbol previously

right?

Then what this symbol could mean? How table should look like.

Here that is the question ?
0
shouldn't both the arrows be from R2 to E2 then?
+1
if both arrow in same direction, then meaning changes. Then it doesnot mean two $E_{2}$ table and in between one $R_{2}$ relation.

Meaning totally changes and it act as single arrow with total participation
0
yes right
so is it referencing?

a table referring to itself
so there should be foreign key then
0
foreign key? why??

Same primary key for both tables.

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