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Доступ до цієї сторінки потребує авторизації. Можна спробувати змінити каталоги.
Applies to:
SQL Server
Azure SQL Database
Azure SQL Managed Instance
Azure Synapse Analytics
Analytics Platform System (PDW)
SQL analytics endpoint in Microsoft Fabric
Warehouse in Microsoft Fabric
SQL database in Microsoft Fabric
This function returns the number of items found in a group. COUNT_BIG operates like the COUNT function. These functions differ only in the data types of their return values. COUNT_BIG always returns a bigint data type value. COUNT always returns an int data type value.
Transact-SQL syntax conventions
Syntax
Aggregation function syntax:
COUNT_BIG ( { [ [ ALL | DISTINCT ] expression ] | * } )
Analytic function syntax:
COUNT_BIG ( { [ ALL ] expression | * } ) OVER ( [ <partition_by_clause> ] )
Arguments
ALL
Applies the aggregate function to all values. ALL serves as the default.
DISTINCT
Specifies that COUNT_BIG returns the number of unique non-null values.
expression
An expression of any type. COUNT_BIG doesn't support aggregate functions or subqueries in an expression.
*
Specifies that COUNT_BIG should count all rows to determine the total table row count to return. COUNT_BIG(*) takes no parameters and doesn't support the use of DISTINCT. COUNT_BIG(*) doesn't require an expression parameter because by definition, it doesn't use information about any particular column. COUNT_BIG(*) returns the number of rows in a specified table, and it preserves duplicate rows. It counts each row separately, including rows that contain null values.
OVER ( [ partition_by_clause ] [ order_by_clause ] )
The partition_by_clause divides the result set produced by the FROM clause into partitions to which the COUNT_BIG function is applied. If you don't specify the partition_by_clause, the function treats all rows of the query result set as a single group. The order_by_clause determines the logical order of the operation. For more information, see OVER clause.
Return types
bigint
Remarks
COUNT_BIG(*) returns the number of items in a group. This count includes NULL values and duplicates.
COUNT_BIG(ALL <expression>) evaluates expression for each row in a group, and returns the number of non-null values.
COUNT_BIG(DISTINCT <expression>) evaluates expression for each row in a group, and returns the number of unique, non-null values.
Deterministic and nondeterministic usage
COUNT_BIG is a deterministic function when used without the OVER and ORDER BY clauses.
COUNT_BIG is nondeterministic when used with the OVER and ORDER BY clauses.
Uses OVER and ORDER BY clauses |
Deterministic |
|---|---|
| No | Yes |
| Yes | No |
For more information, see Deterministic and nondeterministic functions.
Examples
The code samples in this article use the AdventureWorks2025 or AdventureWorksDW2025 sample database, which you can download from the Microsoft SQL Server Samples and Community Projects home page.
A. Use COUNT_BIG and DISTINCT
This example returns the number of different job titles in the HumanResources.Employee table that an employee can hold.
SELECT COUNT_BIG(DISTINCT JobTitle)
FROM HumanResources.Employee;
GO
Here's the result set.
-----------
67
B. Use COUNT_BIG(*)
This example returns the total number of employees in the HumanResources.Employee table.
SELECT COUNT_BIG(*)
FROM HumanResources.Employee;
GO
Here's the result set.
-----------
290
C. Use COUNT_BIG(*) with other aggregates
This example shows that COUNT_BIG(*) works with other aggregate functions in the SELECT list.
SELECT COUNT_BIG(*), AVG(Bonus)
FROM Sales.SalesPerson
WHERE SalesQuota > 25000;
GO
Here's the result set.
------ ---------------------
14 3472.1428
D. Use the OVER clause
This example uses the MIN, MAX, AVG, and COUNT_BIG functions with the OVER clause to return aggregated values for each department in the HumanResources.Department table.
SELECT DISTINCT d.Name,
MIN(eph.Rate) OVER (PARTITION BY edh.DepartmentID) AS MinSalary,
MAX(eph.Rate) OVER (PARTITION BY edh.DepartmentID) AS MaxSalary,
AVG(eph.Rate) OVER (PARTITION BY edh.DepartmentID) AS AvgSalary,
COUNT_BIG(edh.BusinessEntityID) OVER (PARTITION BY edh.DepartmentID) AS EmployeesPerDept
FROM HumanResources.EmployeePayHistory AS eph
INNER JOIN HumanResources.EmployeeDepartmentHistory AS edh
ON eph.BusinessEntityID = edh.BusinessEntityID
INNER JOIN HumanResources.Department AS d
ON d.DepartmentID = edh.DepartmentID
WHERE edh.EndDate IS NULL
ORDER BY d.Name;
Here's the result set.
Name MinSalary MaxSalary AvgSalary EmployeesPerDept
---------------------------- ----------- ----------- ----------- -----------------
Document Control 10.25 17.7885 14.3884 5
Engineering 32.6923 63.4615 40.1442 6
Executive 39.06 125.50 68.3034 4
Facilities and Maintenance 9.25 24.0385 13.0316 7
Finance 13.4615 43.2692 23.935 10
Human Resources 13.9423 27.1394 18.0248 6
Information Services 27.4038 50.4808 34.1586 10
Marketing 13.4615 37.50 18.4318 11
Production 6.50 84.1346 13.5537 195
Production Control 8.62 24.5192 16.7746 8
Purchasing 9.86 30.00 18.0202 14
Quality Assurance 10.5769 28.8462 15.4647 6
Research and Development 40.8654 50.4808 43.6731 4
Sales 23.0769 72.1154 29.9719 18
Shipping and Receiving 9.00 19.2308 10.8718 6
Tool Design 8.62 29.8462 23.5054 6
Examples: Azure Synapse Analytics and Analytics Platform System (PDW)
E. Use COUNT_BIG and DISTINCT
This example returns the number of different titles that an employee of a specific company can hold.
USE ssawPDW;
SELECT COUNT_BIG(DISTINCT Title)
FROM dbo.DimEmployee;
Here's the result set.
-----------
67
F. Use COUNT_BIG(*)
This example returns the total number of rows in the dbo.DimEmployee table.
USE ssawPDW;
SELECT COUNT_BIG(*)
FROM dbo.DimEmployee;
Here's the result set.
-------------
296
G. Use COUNT_BIG(*) with other aggregates
This example combines COUNT_BIG(*) with other aggregate functions in the SELECT list. It returns the number of sales representatives with an annual sales quota greater than $500,000, and the average sales quota of those sales representatives.
USE ssawPDW;
SELECT COUNT_BIG(EmployeeKey) AS TotalCount,
AVG(SalesAmountQuota) AS [Average Sales Quota]
FROM dbo.FactSalesQuota
WHERE SalesAmountQuota > 500000
AND CalendarYear = 2001;
Here's the result set.
TotalCount Average Sales Quota
---------- -------------------
10 683800.0000
H. Use COUNT_BIG with HAVING
This example uses COUNT_BIG with the HAVING clause to return the departments of a company, each of which has more than 15 employees.
USE ssawPDW;
SELECT DepartmentName,
COUNT_BIG(EmployeeKey) AS EmployeesInDept
FROM dbo.DimEmployee
GROUP BY DepartmentName
HAVING COUNT_BIG(EmployeeKey) > 15;
Here's the result set.
DepartmentName EmployeesInDept
-------------- ---------------
Sales 18
Production 179
I. Use COUNT_BIG with OVER
This example uses COUNT_BIG with the OVER clause, to return the number of products contained in each of the specified sales orders.
USE ssawPDW;
SELECT DISTINCT COUNT_BIG(ProductKey) OVER (PARTITION BY SalesOrderNumber) AS ProductCount,
SalesOrderNumber
FROM dbo.FactInternetSales
WHERE SalesOrderNumber IN (N'SO53115', N'SO55981');
Here's the result set.
ProductCount SalesOrderID
------------ -----------------
3 SO53115
1 SO55981