This article provides examples of using the SELECT statement.
The Transact-SQL code samples in this article use the AdventureWorks2022 or AdventureWorksDW2022 sample database, which you can download from the Microsoft SQL Server Samples and Community Projects home page.
The following example shows three code examples. This first code example returns all rows (no WHERE clause is specified) and all columns (using the * ) from the Product table in the AdventureWorks2022 database.
USE AdventureWorks2022; GO SELECT * FROM Production.Product ORDER BY Name ASC; -- Alternate way. USE AdventureWorks2022; GO SELECT p.* FROM Production.Product AS p ORDER BY Name ASC; GO This example returns all rows (no WHERE clause is specified), and only a subset of the columns ( Name , ProductNumber , ListPrice ) from the Product table in the AdventureWorks2022 database. Additionally, a column heading is added.
USE AdventureWorks2022; GO SELECT Name, ProductNumber, ListPrice AS Price FROM Production.Product ORDER BY Name ASC; GO This example returns only the rows for Product that have a product line of R and that have days to manufacture that is less than 4 .
USE AdventureWorks2022; GO SELECT Name, ProductNumber, ListPrice AS Price FROM Production.Product WHERE ProductLine = 'R' AND DaysToManufacture < 4 ORDER BY Name ASC; GO The following examples return all rows from the Product table. The first example returns total sales and the discounts for each product. In the second example, the total revenue is calculated for each product.
USE AdventureWorks2022; GO SELECT p.Name AS ProductName, NonDiscountSales = (OrderQty * UnitPrice), Discounts = ((OrderQty * UnitPrice) * UnitPriceDiscount) FROM Production.Product AS p INNER JOIN Sales.SalesOrderDetail AS sod ON p.ProductID = sod.ProductID ORDER BY ProductName DESC; GO This is the query that calculates the revenue for each product in each sales order.
USE AdventureWorks2022; GO SELECT 'Total income is', ((OrderQty * UnitPrice) * (1.0 - UnitPriceDiscount)), ' for ', p.Name AS ProductName FROM Production.Product AS p INNER JOIN Sales.SalesOrderDetail AS sod ON p.ProductID = sod.ProductID ORDER BY ProductName ASC; GO The following example uses DISTINCT to prevent the retrieval of duplicate titles.
USE AdventureWorks2022; GO SELECT DISTINCT JobTitle FROM HumanResources.Employee ORDER BY JobTitle; GO The following first example creates a temporary table named #Bicycles in tempdb .
USE tempdb; GO IF OBJECT_ID(N'#Bicycles', N'U') IS NOT NULL DROP TABLE #Bicycles; GO SELECT * INTO #Bicycles FROM AdventureWorks2022.Production.Product WHERE ProductNumber LIKE 'BK%'; GO This second example creates the permanent table NewProducts .
USE AdventureWorks2022; GO IF OBJECT_ID('dbo.NewProducts', 'U') IS NOT NULL DROP TABLE dbo.NewProducts; GO ALTER DATABASE AdventureWorks2022 SET RECOVERY BULK_LOGGED; GO SELECT * INTO dbo.NewProducts FROM Production.Product WHERE ListPrice > $25 AND ListPrice < $100; GO ALTER DATABASE AdventureWorks2022 SET RECOVERY FULL; GO A correlated subquery is a query that depends on the outer query for its values. This query can be executed repeatedly, one time for each row that could be selected by the outer query.
The first example shows queries that are semantically equivalent to illustrate the difference between using the EXISTS keyword and the IN keyword. Both are examples of a valid subquery that retrieves one instance of each product name for which the product model is a long sleeve logo jersey, and the ProductModelID numbers match between the Product and ProductModel tables.
USE AdventureWorks2022; GO SELECT DISTINCT Name FROM Production.Product AS p WHERE EXISTS ( SELECT * FROM Production.ProductModel AS pm WHERE p.ProductModelID = pm.ProductModelID AND pm.Name LIKE 'Long-Sleeve Logo Jersey%' ); GO -- OR USE AdventureWorks2022; GO SELECT DISTINCT Name FROM Production.Product WHERE ProductModelID IN ( SELECT ProductModelID FROM Production.ProductModel AS pm WHERE p.ProductModelID = pm.ProductModelID AND Name LIKE 'Long-Sleeve Logo Jersey%' ); GO The next example uses IN and retrieves one instance of the first name and family name of each employee for which the bonus in the SalesPerson table is 5000.00 , and for which the employee identification numbers match in the Employee and SalesPerson tables.
USE AdventureWorks2022; GO SELECT DISTINCT p.LastName, p.FirstName FROM Person.Person AS p INNER JOIN HumanResources.Employee AS e ON e.BusinessEntityID = p.BusinessEntityID WHERE 5000.00 IN ( SELECT Bonus FROM Sales.SalesPerson AS sp WHERE e.BusinessEntityID = sp.BusinessEntityID ); GO The previous subquery in this statement can't be evaluated independently of the outer query. It requires a value for Employee.EmployeeID , but this value changes as the SQL Server Database Engine examines different rows in Employee .
A correlated subquery can also be used in the HAVING clause of an outer query. This example finds the product models for which the maximum list price is more than twice the average for the model.
USE AdventureWorks2022; GO SELECT p1.ProductModelID FROM Production.Product AS p1 GROUP BY p1.ProductModelID HAVING MAX(p1.ListPrice) >= ( SELECT AVG(p2.ListPrice) * 2 FROM Production.Product AS p2 WHERE p1.ProductModelID = p2.ProductModelID ); GO This example uses two correlated subqueries to find the names of employees who sold a particular product.
USE AdventureWorks2022; GO SELECT DISTINCT pp.LastName, pp.FirstName FROM Person.Person pp INNER JOIN HumanResources.Employee e ON e.BusinessEntityID = pp.BusinessEntityID WHERE pp.BusinessEntityID IN ( SELECT SalesPersonID FROM Sales.SalesOrderHeader WHERE SalesOrderID IN ( SELECT SalesOrderID FROM Sales.SalesOrderDetail WHERE ProductID IN ( SELECT ProductID FROM Production.Product p WHERE ProductNumber = 'BK-M68B-42' ) ) ); GO The following example finds the total of each sales order in the database.
USE AdventureWorks2022; GO SELECT SalesOrderID, SUM(LineTotal) AS SubTotal FROM Sales.SalesOrderDetail GROUP BY SalesOrderID ORDER BY SalesOrderID; GO Because of the GROUP BY clause, only one row containing the sum of all sales is returned for each sales order.
The following example finds the average price and the sum of year-to-date sales, grouped by product ID and special offer ID.
USE AdventureWorks2022; GO SELECT ProductID, SpecialOfferID, AVG(UnitPrice) AS [Average Price], SUM(LineTotal) AS SubTotal FROM Sales.SalesOrderDetail GROUP BY ProductID, SpecialOfferID ORDER BY ProductID; GO The following example puts the results into groups after retrieving only the rows with list prices greater than $1000 .
USE AdventureWorks2022; GO SELECT ProductModelID, AVG(ListPrice) AS [Average List Price] FROM Production.Product WHERE ListPrice > $1000 GROUP BY ProductModelID ORDER BY ProductModelID; GO The following example groups by an expression. You can group by an expression if the expression doesn't include aggregate functions.
USE AdventureWorks2022; GO SELECT AVG(OrderQty) AS [Average Quantity], NonDiscountSales = (OrderQty * UnitPrice) FROM Sales.SalesOrderDetail GROUP BY (OrderQty * UnitPrice) ORDER BY (OrderQty * UnitPrice) DESC; GO The following example finds the average price of each type of product and orders the results by average price.
USE AdventureWorks2022; GO SELECT ProductID, AVG(UnitPrice) AS [Average Price] FROM Sales.SalesOrderDetail WHERE OrderQty > 10 GROUP BY ProductID ORDER BY AVG(UnitPrice); GO The first example that follows shows a HAVING clause with an aggregate function. It groups the rows in the SalesOrderDetail table by product ID and eliminates products whose average order quantities are five or less. The second example shows a HAVING clause without aggregate functions.
USE AdventureWorks2022; GO SELECT ProductID FROM Sales.SalesOrderDetail GROUP BY ProductID HAVING AVG(OrderQty) > 5 ORDER BY ProductID; GO This query uses the LIKE clause in the HAVING clause.
USE AdventureWorks2022; GO SELECT SalesOrderID, CarrierTrackingNumber FROM Sales.SalesOrderDetail GROUP BY SalesOrderID, CarrierTrackingNumber HAVING CarrierTrackingNumber LIKE '4BD%' ORDER BY SalesOrderID ; GO The following example shows using GROUP BY , HAVING , WHERE , and ORDER BY clauses in one SELECT statement. It produces groups and summary values but does so after eliminating the products with prices over $25 and average order quantities under 5. It also organizes the results by ProductID .
USE AdventureWorks2022; GO SELECT ProductID FROM Sales.SalesOrderDetail WHERE UnitPrice < 25.00 GROUP BY ProductID HAVING AVG(OrderQty) >5 ORDER BY ProductID; GO The following example groups the SalesOrderDetail table by product ID and includes only those groups of products that have orders totaling more than $1000000.00 and whose average order quantities are less than 3 .
USE AdventureWorks2022; GO SELECT ProductID, AVG(OrderQty) AS AverageQuantity, SUM(LineTotal) AS Total FROM Sales.SalesOrderDetail GROUP BY ProductID HAVING SUM(LineTotal) > $1000000.00 AND AVG(OrderQty) < 3; GO To see the products with total sales greater than $2000000.00 , use this query:
USE AdventureWorks2022; GO SELECT ProductID, Total = SUM(LineTotal) FROM Sales.SalesOrderDetail GROUP BY ProductID HAVING SUM(LineTotal) > $2000000.00; GO If you want to make sure there are at least 1,500 items involved in the calculations for each product, use HAVING COUNT(*) > 1500 to eliminate the products that return totals for fewer than 1500 items sold. The query looks like this:
USE AdventureWorks2022; GO SELECT ProductID, SUM(LineTotal) AS Total FROM Sales.SalesOrderDetail GROUP BY ProductID HAVING COUNT(*) > 1500; GO The following example shows two ways to use the INDEX optimizer hint. The first example shows how to force the optimizer to use a nonclustered index to retrieve rows from a table. The second example forces a table scan by using an index of 0.
USE AdventureWorks2022; GO SELECT pp.FirstName, pp.LastName, e.NationalIDNumber FROM HumanResources.Employee AS e WITH (INDEX (AK_Employee_NationalIDNumber)) INNER JOIN Person.Person AS pp ON e.BusinessEntityID = pp.BusinessEntityID WHERE LastName = 'Johnson'; GO -- Force a table scan by using INDEX = 0. USE AdventureWorks2022; GO SELECT pp.LastName, pp.FirstName, e.JobTitle FROM HumanResources.Employee AS e WITH (INDEX = 0) INNER JOIN Person.Person AS pp ON e.BusinessEntityID = pp.BusinessEntityID WHERE LastName = 'Johnson'; GO The following example shows how the OPTION (GROUP) clause is used with a GROUP BY clause.
USE AdventureWorks2022; GO SELECT ProductID, OrderQty, SUM(LineTotal) AS Total FROM Sales.SalesOrderDetail WHERE UnitPrice < $5.00 GROUP BY ProductID, OrderQty ORDER BY ProductID, OrderQty OPTION (HASH GROUP, FAST 10); GO The following example uses the MERGE UNION query hint.
USE AdventureWorks2022; GO SELECT BusinessEntityID, JobTitle, HireDate, VacationHours, SickLeaveHours FROM HumanResources.Employee AS e1 UNION SELECT BusinessEntityID, JobTitle, HireDate, VacationHours, SickLeaveHours FROM HumanResources.Employee AS e2 OPTION (MERGE UNION); GO In the following example, the result set includes the contents of the ProductModelID and Name columns of both the ProductModel and Gloves tables.
USE AdventureWorks2022; GO IF OBJECT_ID('dbo.Gloves', 'U') IS NOT NULL DROP TABLE dbo.Gloves; GO -- Create Gloves table. SELECT ProductModelID, Name INTO dbo.Gloves FROM Production.ProductModel WHERE ProductModelID IN (3, 4); GO -- Here is the simple union. USE AdventureWorks2022; GO SELECT ProductModelID, Name FROM Production.ProductModel WHERE ProductModelID NOT IN (3, 4) UNION SELECT ProductModelID, Name FROM dbo.Gloves ORDER BY Name; GO In the following example, the INTO clause in the second SELECT statement specifies that the table named ProductResults holds the final result set of the union of the designated columns of the ProductModel and Gloves tables. The Gloves table is created in the first SELECT statement.
USE AdventureWorks2022; GO IF OBJECT_ID('dbo.ProductResults', 'U') IS NOT NULL DROP TABLE dbo.ProductResults; GO IF OBJECT_ID('dbo.Gloves', 'U') IS NOT NULL DROP TABLE dbo.Gloves; GO -- Create Gloves table. SELECT ProductModelID, Name INTO dbo.Gloves FROM Production.ProductModel WHERE ProductModelID IN (3, 4); GO USE AdventureWorks2022; GO SELECT ProductModelID, Name INTO dbo.ProductResults FROM Production.ProductModel WHERE ProductModelID NOT IN (3, 4) UNION SELECT ProductModelID, Name FROM dbo.Gloves; GO SELECT ProductModelID, Name FROM dbo.ProductResults; The order of certain parameters used with the UNION clause is important. The following example shows the incorrect and correct use of UNION in two SELECT statements in which a column is to be renamed in the output.
USE AdventureWorks2022; GO IF OBJECT_ID('dbo.Gloves', 'U') IS NOT NULL DROP TABLE dbo.Gloves; GO -- Create Gloves table. SELECT ProductModelID, Name INTO dbo.Gloves FROM Production.ProductModel WHERE ProductModelID IN (3, 4); GO /* INCORRECT */ USE AdventureWorks2022; GO SELECT ProductModelID, Name FROM Production.ProductModel WHERE ProductModelID NOT IN (3, 4) ORDER BY Name UNION SELECT ProductModelID, Name FROM dbo.Gloves; GO /* CORRECT */ USE AdventureWorks2022; GO SELECT ProductModelID, Name FROM Production.ProductModel WHERE ProductModelID NOT IN (3, 4) UNION SELECT ProductModelID, Name FROM dbo.Gloves ORDER BY Name; GO The following examples use UNION to combine the results of three tables that all have the same five rows of data. The first example uses UNION ALL to show the duplicated records, and returns all 15 rows. The second example uses UNION without ALL to eliminate the duplicate rows from the combined results of the three SELECT statements, and returns five rows.
The third example uses ALL with the first UNION and parentheses enclose the second UNION that isn't using ALL . The second UNION is processed first because it's in parentheses, and returns five rows because the ALL option isn't used and the duplicates are removed. These five rows are combined with the results of the first SELECT by using the UNION ALL keywords. This example doesn't remove the duplicates between the two sets of five rows. The final result has 10 rows.
USE AdventureWorks2022; GO IF OBJECT_ID('dbo.EmployeeOne', 'U') IS NOT NULL DROP TABLE dbo.EmployeeOne; GO IF OBJECT_ID('dbo.EmployeeTwo', 'U') IS NOT NULL DROP TABLE dbo.EmployeeTwo; GO IF OBJECT_ID('dbo.EmployeeThree', 'U') IS NOT NULL DROP TABLE dbo.EmployeeThree; GO SELECT pp.LastName, pp.FirstName, e.JobTitle INTO dbo.EmployeeOne FROM Person.Person AS pp INNER JOIN HumanResources.Employee AS e ON e.BusinessEntityID = pp.BusinessEntityID WHERE LastName = 'Johnson'; GO SELECT pp.LastName, pp.FirstName, e.JobTitle INTO dbo.EmployeeTwo FROM Person.Person AS pp INNER JOIN HumanResources.Employee AS e ON e.BusinessEntityID = pp.BusinessEntityID WHERE LastName = 'Johnson'; GO SELECT pp.LastName, pp.FirstName, e.JobTitle INTO dbo.EmployeeThree FROM Person.Person AS pp INNER JOIN HumanResources.Employee AS e ON e.BusinessEntityID = pp.BusinessEntityID WHERE LastName = 'Johnson'; GO -- Union ALL SELECT LastName, FirstName, JobTitle FROM dbo.EmployeeOne UNION ALL SELECT LastName, FirstName, JobTitle FROM dbo.EmployeeTwo UNION ALL SELECT LastName, FirstName, JobTitle FROM dbo.EmployeeThree; GO SELECT LastName, FirstName, JobTitle FROM dbo.EmployeeOne UNION SELECT LastName, FirstName, JobTitle FROM dbo.EmployeeTwo UNION SELECT LastName, FirstName, JobTitle FROM dbo.EmployeeThree; GO SELECT LastName, FirstName, JobTitle FROM dbo.EmployeeOne UNION ALL ( SELECT LastName, FirstName, JobTitle FROM dbo.EmployeeTwo UNION SELECT LastName, FirstName, JobTitle FROM dbo.EmployeeThree ); GO