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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

in Databases by Veteran (116k points) | 84 views

what does that arrow from R1 to E2 indicates?
I know arrow from entity to relationship indicates 0 or 1 participation

yes, arrow means m:1 partial participation


here the arrow is from relationship to entity

arrow from entity to relationship means m:1

where u got that?

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

nothing more :
then why is there arrow from entity E2 to relationship R2?
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


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

Here that is the question ?
shouldn't both the arrows be from R2 to E2 then?
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
yes right
so is it referencing?

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

Same primary key for both tables.

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