Menu
I have two tables: Employee (ID, Name, Address) and Store(ID,Address) and I would like to record information about people who work in each store.
I thought of making a new table called Employee_List table. My questions:
1- Employee_List and Employee has one-to-many relation, right?
2- Employee_list to store has one-to-one relation, right?
3- How to define foreign and primary keys for Employee_List table?
831
The join is done by the JOIN operator. In the FROM clause, the name of the first table ( product ) is followed by a JOIN keyword then by the name of the second table ( category ). This is then followed by the keyword ON and by the condition for joining the rows from the different tables.
In SQL Server, you can join more than two tables in either of two ways: by using a nested JOIN , or by using a WHERE clause. Joins are always done pair-wise.
To combine tables we will use the UNION, UNION ALL, INNER JOIN, LEFT OUTER JOIN and RIGHT OUTER JOIN keywords.
Link tables are usually association/bridge tables between different Hub tables in Datavault. They mostly resolve many to many relation between different Hub tables. Example. Link - INVOICE_LINE_ITEM. Hub - INVOICE, PRODUCT etc.
Linking tablesTwo tables are linked when they have a matching field, that is, a field in each table containing similar data. For example, suppose you want to link a Suppliers table with another table called Products. Both tables must have at least one field in common.
Employee_list should have:
I would recommend changing the table name to represent the composite table, i.e.
EmployeeStores. This would allow your schema to be scalable, employees can work in multiple stores.
In SQL Server:
CREATE TABLE EmployeeStores
(
EMPLOYEEStoreID INT IDENTITY,
EMPLOYEEID INT FOREIGN KEY REFERENCES Employee(employee_id),
STOREID INT FOREIGN KEY REFERENCES Store(store_id)
)
If you love us? You can donate to us via Paypal or buy me a coffee so we can maintain and grow! Thank you!
Donate Us With
