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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What is SQL? Explain with query example

SQL (Structured Query Language) is a programming language used for managing and manipulating relational databases. It allows users to interact with databases by querying and manipulating data. Let's illustrate SQL with a simple query example:

Consider a database with a table named "Employees" that stores information about employees in a company. The table has the following columns: "EmployeeID," "FirstName," "LastName," "Department," and "Salary."

To retrieve the names of all employees in the "Sales" department, you can use the following SQL query:


SELECT FirstName, LastName
FROM Employees
WHERE Department = 'Sales';

Let's break down the query:

SELECT: The SELECT statement specifies the columns you want to retrieve from the database. In this case, we want to retrieve the "FirstName" and "LastName" columns.

FROM: The FROM clause indicates the table from which the data will be retrieved. In this case, we want to retrieve data from the "Employees" table.

WHERE: The WHERE clause is used to specify conditions for filtering the data. Here, we want to retrieve employees only from the "Sales" department, so we specify Department = 'Sales' as the condition.

The result of this query will be a list of the first names and last names of all employees in the "Sales" department.

Here's an example of how the result might look:


FirstName  | LastName
---------------------
John       | Doe
Jane       | Smith

This is a basic example of an SQL query. SQL provides a wide range of capabilities, including complex queries involving joins, aggregations, sorting, and more. SQL is not only used for querying data but also for inserting, updating, and deleting data, creating and modifying database schemas, managing permissions, and performing other database-related tasks.

The specific syntax and features of SQL can vary slightly between different database management systems, but the core concepts and functionality remain consistent.

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