SQL Server BasicsWhat is SQL Server database?What is RDBMS?What is Normalization?Why we use Denormalization?What_is_SQL?What is PL/SQL?Difference between SQL and PL/SQLDatabase TableOne to One RelationshipOne to Many RelationshipMany to Many RelationshipMany to One RelationshipString Data TypesNumber Data TypesDate Data TypesOther Data TypesCreate DatabaseDrop DatabaseCreating and Managing Users in SQL ServerCreate TableAlter TableDrop TableConstraints in SQL serverPrimary KeyForeign KeyUnique KeyCandidate KeyComposite KeyDifference between primary key and candidate keyPrimary key and foreign key relationshipSurrogate KeyCascading Referential Integrity ConstraintsSelf Referential Integrity ConstraintsInsert into statementInsert multiple recordsUpdate statementDelete statementTruncate statementDifference between Delete and TruncateAlias in SQL ServerSelect statementSelect DistinctSelect TopSelect IntoNull Functions(ISNULL(),NULLIF(),COALESCE())Sub QueryIdentity ColumnSequence objectDifference between sequence and identity columnSQL Server ClausesWHERE ClauseOrder By ClauseTop N ClauseGroup By ClauseHaving ClauseDifference between Where and HavingSQL Server OperatorsArithmetic OperatorsComparison OperatorsLogical OperatorsBitwise OperatorsAny OperatorsAll OperatorsUnion OperatorsUnion All OperatorsDifference between Union and Union AllIntersect OperatorExcept OperatorDifference between Except and IntersectJoinsInner JoinLeft JoinRight JoinFull JoinSelf JoinCross JoinViewsWhat are views?Create views using SSMSIndexed ViewsComplex ViewsCheck Option in ViewCheck Encryption in ViewSchema Binding Option in ViewRead-only ViewsUpdatable ViewsAdvantages and disadvantages of viewsCreate multiple views on one tableCan we implement index on views?Can we Perform Insert, update, delete operation on views?Stored Procedure and FunctionsWhat are Stored Procedures?Why we use stored procedures?Passing parameters to Stored procedureUser-Defined FunctionsDifference between UDF and Stored procedurePre-Defined Functions@@Indentity and Scope_IndentityNULLIF, ISNULL and COALESCE
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SQL - Many to One Relationship

A many-to-one relationship in a database refers to a relationship between two entities where multiple records in one entity can be associated with a single record in the other entity. It represents a one-way relationship where the "many" side relates to the "one" side.

Let's consider an example of a database for a company's employees and their departments. Suppose we have two tables: "Employees" and "Departments." Many employees can belong to a single department, but each employee can only belong to one department. This represents a many-to-one relationship between the "Employees" and "Departments" tables.

Here's a simplified representation of the two tables:

Table: Employees
EmployeeID EmployeeName DepartmentID
1 John Doe 1
2 Jane Smith 2
3 Mark Johnson 1
Table: Departments
DepartmentID Name
1 Sales
2 Finance

In this example, multiple employees in the "Employees" table can belong to a single department in the "Departments" table. For instance, John Doe (EmployeeID 1) and Mark Johnson (EmployeeID 3) both belong to the "Sales" department (DepartmentID 1), while Jane Smith (EmployeeID 2) belongs to the "Finance" department (DepartmentID 2).

This many-to-one relationship allows for efficient organization and retrieval of data. It enables us to associate multiple employees with a single department, making it easier to manage and analyze employee data based on departmental divisions.

Many-to-one relationships are commonly used in various database scenarios, such as the relationship between customers and orders in an e-commerce system, where many orders can be placed by a single customer, but each order belongs to only one customer.

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