0
Relationships happen between two tables.
One to Many means that one objects (called tuples, or rows) of Table A is related to one or more objects in Table B.
For example, if a doctor can work only in one hospital, and we have a table of hospitals and a table of doctors, Hospitals has a One to Many relationship with Doctors, because for each hospital you will have one or more doctors working at it.
Many to Many means that for each object in Table A, one or more objects in Table B are associated, and viceversa.
In the example, if doctors are allowed to work in different hospitals, the table Hospitals and the table Doctors have a Many to Many relationship.
Now, how to implement this in a relationship DB, that is another question.
Add your answer:
Earn +20 pts
What is the most common type of relationship between tables in a relational database?
one-to-many relationship
What is one to many relationship in database er diagram?
A one-to-many relationship means that one row in one of the tables will relate directly to many rows in the other table.
Distinguish between a relation and a relationship in database?
Relation is one record in the database or a tuple. Relationship is that how tables are connected to each other.
How do you convert many to many to one to many in database?
The way a many to many relationship is done is by inserting a junction table and having two one to many relationships with the primary key of each of the two main tables becoming a join primary key of the junction table.
How are relationship between tables expressed in a relational database?
Tables are the basic building blocks of a relational database.
Why many to many relationship does not exist in Msaccess?
Many to many relationships do exist in Microsoft Access. A many to many relationship in any database is done by creating a junction table and linking it to two other tables. A many to many relationship is a combination of two one to many relationships. This can be done in any relational database, including Microsoft Access.
How Many to Many Relationship is being developed in ER data model?
Database is the collection records . There are three types of relationships in DB : one to one , one to many, many to many.
What is an Entity Relationship diagram for library management database?
An entity relationship diagram is a graphical documentation of a database's tables, fields, and the relationships between tables in the database. It shows all of the fields in each of the tables, and sometimes describes the data types for those fields as well as having lines between the tables that show relationships. The relationships can be one-to-many, or one-to-one relationships. A one-to-many (the most common) relationship means that one row in one of the tables will relate directly to many rows in the other table (hence the reason the data is in two tables.) One-to-one relationships are use to separate data that could be located in the same table as the other data into multiple tables.Entity relationship diagrams are helpful when querying a database as well to understand how to write the SQL to pull the data out of the database. These diagrams are useful to database designers, database administrators, computer programmers, and database users to understand the structure of the database.------------------------------------------------------------------------------------------------------------------hiii i m mehul, frnds m giving a er diagram for library management, ok..check out here, its gud..http://www.kdd.uncc.edu/Cynthia/3160Proj/Report_Final.pdfand this has all dfds, erds, class diagrams n all..http://www.docstoc.com/docs/9375857/library-mangment-system-anlysis-anddesginhave a bright carrier-------------------------------------------------------------------------------------------------------------------
What are predicates that define correct database states and relationship with in database?
schema
1 to many relation?
Here is an example from Microsoft: Each customer can have many orders but each order belongs to a single customer. In relational database terminology, this is referred to as a one-to-many relationship.
What is DBMS relationship?
1.what is a Relationship in database management system?
What is the typical language for database management?
The typical language for database management is SQL. This is one of many programming languages, but this is the predominate one for database management.
What is a connection within the data in a database?
relationship
What is client-server database?
A client-server database is the relationship between two computer programs. One makes a service request (client) and the other (server) fulfills the request.
Is the association relationship one-to-one one-to-many or many-to-many?
one-to-one relationship in adatabase
How many tables are required in access database?
one
How many Access database can you have open at one time?
as many as you want
