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WSZYSTKIE (języka Transact-SQL)

Compares a scalar value with a single-column set of values.

Topic link iconTransact-SQL Syntax Conventions

scalar_expression { = | <> | != | > | >= | !> | < | <= | !< } ALL ( subquery )

Arguments

  • scalar_expression
    Is any valid expression.

  • { = | <> | != | > | >= | !> | < | <= | !< }
    Is a comparison operator.

  • subquery
    Is a subquery that returns a result set of one column. The data type of the returned column must be the same data type as the data type of scalar_expression.

    Is a restricted SELECT statement, in which the ORDER BY clause, the COMPUTE clause, and the INTO keyword are not allowed.

Result Types

Boolean

Result Value

Returns TRUE when the comparison specified is TRUE for all pairs (scalar_expression**,**x), when x is a value in the single-column set; otherwise returns FALSE.

Remarks

ALL requires the scalar_expression to compare positively to every value that is returned by the subquery. For instance, if the subquery returns values of 2 and 3, scalar_expression <= ALL (subquery) would evaluate as TRUE for a scalar_expression of 2. If the subquery returns values of 2 and 3, scalar_expression = ALL (subquery) would evaluate as FALSE, because some of the values of the subquery (the value of 3) would not meet the criteria of the expression.

For statements that require the scalar_expression to compare positively to only one value that is returned by the subquery, see Niektóre | ANY (języka Transact-SQL).

This topic refers to ALL when it is used with a subquery. ALL can also be used with UNION and SELECT.

Examples

The following example creates a stored procedure that determines whether all the components of a specified SalesOrderID in the AdventureWorks database can be manufactured in the specified number of days. The example uses a subquery to create a list of the number of DaysToManufacture value for all of the components of the specific SalesOrderID, and then confirms that all the DaysToManufacture are within the number of days specified.

USE AdventureWorks ;
GO

CREATE PROCEDURE DaysToBuild @OrderID int, @NumberOfDays int
AS
IF 
@NumberOfDays >= ALL
   (
    SELECT DaysToManufacture
    FROM Sales.SalesOrderDetail
    JOIN Production.Product 
    ON Sales.SalesOrderDetail.ProductID = Production.Product.ProductID 
    WHERE SalesOrderID = @OrderID
   )
PRINT 'All items for this order can be manufactured in specified number of days or less.'
ELSE 
PRINT 'Some items for this order cannot be manufactured in specified number of days or less.' ;

To test the procedure, execute the procedure by using the SalesOrderID 49080, which has one component requiring 2 days and two components that require 0 days. The first statement below meets the criteria. The second query does not.

EXECUTE DaysToBuild 49080, 2 ;

Here is the result set.

All items for this order can be manufactured in specified number of days or less.

EXECUTE DaysToBuild 49080, 1 ;

Here is the result set.

Some items for this order cannot be manufactured in specified number of days or less.