我有一个存储过程,用于检查将在接下来的 90、60、30、21、14 和 7 天内到期的卡。当我在 SQL Server 中执行存储过程时,我得到了所有的行,但是当我从代码中调用相同的存储过程时,它只返回第一行而不循环整个结果集。
这是我检索结果的方式:
SELECT AVG(t1.Score * 1.0)
在我调用的代码中:
CREATE PROCEDURE [dbo].[GetExpiringCards]
AS
DECLARE @today datetime2 = CAST(GETDATE() AS date)
DECLARE @INTERVALS TABLE (intval int)
INSERT INTO @INTERVALS (intval) VALUES (90)
INSERT INTO @INTERVALS (intval) VALUES (60)
INSERT INTO @INTERVALS (intval) VALUES (30)
INSERT INTO @INTERVALS (intval) VALUES (21)
INSERT INTO @INTERVALS (intval) VALUES (7)
INSERT INTO @INTERVALS (intval) VALUES (14)
DECLARE @value int
DECLARE db_cursor CURSOR FOR
SELECT intval FROM @INTERVALS
OPEN db_cursor
FETCH NEXT FROM db_cursor INTO @value
WHILE @@FETCH_STATUS = 0
BEGIN
SET NOCOUNT ON;
SELECT
@value AS Interval, DATEADD(DD, @value, @today) AS ExpiresOn,
CustomerId, IssueBranch
FROM
Cards
WHERE
ExpiryDate = CONVERT(DATE, DATEADD(DAY, @value, GETDATE()))
FETCH NEXT FROM db_cursor INTO @value
END
CLOSE db_cursor
DEALLOCATE db_cursor
GO
当我在 SSMS 中执行存储过程时,我得到以下信息:
我尝试更改如下逻辑,但一旦获取第一行,流程就会立即循环:
using (SqlConnection conn = new SqlConnection(DatabaseConnect2))
{
SqlCommand cmd = new SqlCommand("GetExpiringCards", conn);
cmd.CommandType = CommandType.StoredProcedure;
conn.Open();
SqlDataReader dr = cmd.ExecuteReader();
while (dr.Read())
{
Customer customer = new Customer ();
customer.Interval = Convert.ToInt32(dr["Interval"]);
customer.ExpiresOn = Convert.ToDateTime(dr["ExpiresOn"]);
customer.CustomerId = Convert.ToString(dr["CustomerId"]);
customer.IssueBranch = Convert.ToString(dr["IssueBranch"]);
customer.Add(upload);
}
conn.Close();
}
我错过了什么?
答案 0 :(得分:3)
每个 FETCH
返回一行作为结果集返回给应用程序。尽管您可以更改 C# 代码来处理该问题(即 dr.NextResult()
),但最好在单个查询中返回所有行。下面是一个单语句示例,它也使用 table value constructor 代替表变量。
CREATE PROCEDURE [dbo].[GetExpiringCards]
AS
SET NOCOUNT ON;
SELECT
i.value AS Interval
, DATEADD(DD,value,GETDATE()) AS ExpiresOn
, CustomerId, IssueBranch
FROM Cards AS c
CROSS JOIN (SELECT value FROM (VALUES(90),(60),(30),(21),(7),(14)) AS intervals(value)) AS i
WHERE c.ExpiryDate=CONVERT(DATE, DATEADD(DAY, i.value, GETDATE()));