CURSOR_STATUS
这是一个标量函数,该函数允许存储过程的调用方确定针对一个给定参数,该过程是否返回游标和结果集。语法
CURSOR_STATUS
(
{ 'local' , 'cursor_name' }
| { 'global' , 'cursor_name' }
| { 'variable' , 'cursor_variable' }
)
这是一个标量函数,该函数允许存储过程的调用方确定针对一个给定参数,该过程是否返回游标和结果集。语法
CURSOR_STATUS
(
{ 'local' , 'cursor_name' }
| { 'global' , 'cursor_name' }
| { 'variable' , 'cursor_variable' }
)
下面的示例创建一个名为 lake_list 的过程,并将执行 lake_list 的输出结果用作 CURSOR_STATUS 的检验。说明 本示例依赖于一个名为 check_authority 的过程,该过程尚未创建。
USE pubs
IF EXISTS (SELECT name FROM sysobjects
WHERE name = 'lake_list' AND type = 'P')
DROP PROCEDURE lake_list
GO
CREATE PROCEDURE lake_list
( @region varchar(30),
@size integer,
@lake_list_cursor CURSOR VARYING OUTPUT )
AS
BEGIN
DECLARE @ok SMALLINT
EXECUTE check_authority @region, username, @ok OUTPUT
IF @ok = 1
BEGIN
SET @lake_list_cursor =CURSOR LOCAL SCROLL FOR
SELECT name, lat, long, size, boat_launch, cost
FROM lake_inventory
WHERE locale = @region AND area >= @size
ORDER BY name
OPEN @lake_list_cursor
END
END
DECLARE @my_lakes_cursor CURSOR
DECLARE @my_region char(30)
SET @my_region = 'Northern Ontario'
EXECUTE lake_list @my_region, 500, @my_lakes_cursor OUTPUT
IF Cursor_Status('variable', '@my_lakes_cursor') <= 0
BEGIN
/* Some code to tell the user that there is no list of
lakes for him/her */
END
ELSE
BEGIN
FETCH @my_lakes_cursor INTO -- Destination here
-- Continue with other code here.
END