What is complex join? Difference with Foreign key Primary Key join?
Complex joins are joins which have following diffrences from a PK-FK joins
# Complex joins can have conditional mappings like >,<,>=,NOT,AND,etc apart from '=' whereas the PK-FK joins are always '='.
# PK-FK joins are always (1-N), whereas complex joins can have (1 - 0,1) and (0,1 - N) kind of relationships
PK-FK is always 1-N and complex joins can have (1-0,1) and (0,1-N).
PK-FK is always 1-N and complex joins can have (1-0,1) and (0,1-N).
as per my knowledge i understand that 1-N is one -- many relation .
complex join:- complex join are used in physical layer in between two tables where ever that do not involved primary key and forgin key relationship.
Foregin Key:- by using the forgin key we can define the joins between two tables. joins between is 1:M or M:M. if we want to define many:many relationship we have to use bridge tables.
how to configure the complex join? Ans: complex join is that join within join where as two tables doesn't have any foreign key means at that time complex join is used
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