如何更新满足SQL server中SELECT语句内条件的特定行的值
我有像“床”和“绳子”这样的桌子。我想为患者分配一张空床(即从床位表以status=“Available”进行出价),然后将出价状态更改为“已占用”。请帮忙。以下是我当前的查询,但我不确定如何继续如何更新满足SQL server中SELECT语句内条件的特定行的值,sql,sql-server,sql-server-2012,Sql,Sql Server,Sql Server 2012,我有像“床”和“绳子”这样的桌子。我想为患者分配一张空床(即从床位表以status=“Available”进行出价),然后将出价状态更改为“已占用”。请帮忙。以下是我当前的查询,但我不确定如何继续 update Patient_Record set b_ID = (select top 1 b_ID from bed where Status_Avai_Occ = 'Available') /*i want to change the status of this b_ID to "Occup
update Patient_Record
set b_ID = (select top 1 b_ID from bed where Status_Avai_Occ = 'Available')
/*i want to change the status of this b_ID to "Occupied"*/
where Admission_Type = 'In Patient'
这将使用患者的入院类型更新所有患者记录 我不确定我是否完全理解您的结构,但您可以这样做:
DECLARE @AvailableBID INT
SELECT TOP 1 @AvailableBID = b_ID FROM bed WHERE Status_Avai_Occ = 'Available'
UPDATE Patient_Record
SET b_ID = @AvailableBID
WHERE Admission_Type = 'In Patient'
UPDATE bed
SET Status_Avai_occ = 'Occupied'
WHERE b_ID = @AvailableBid
注意:这仍将使用患者中的入院类型更新所有患者记录。您将需要应用一个附加过滤器,即行号
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DECLARE @AvailableBID INT
DECLARE @AvailablePatientRecord INT
SELECT TOP 1 @AvailableBID = b_ID FROM bed WHERE Status_Avai_Occ = 'Available'
SELECT TOP 1 @AvailablePatientRecord = PatientRecordId FROM Patient_Record WHERE Admission_Type = 'In Patient'
UPDATE Patient_Record
SET b_ID = @AvailableBID
WHERE PatientRecordId = @AvailablePatientRecord
UPDATE bed
SET Status_Avai_occ = 'Occupied'
WHERE b_ID = @AvailableBid
注意:您必须确保在患者记录表中有一个PatientRecord,SQL Server不允许您在一个update语句中更新多个表,但是您可以在一个事务中简单地包装这两个更新,如下所示:
DECLARE @b_ID INT
SELECT TOP 1 @b_ID = b_ID FROM bed WHERE Status_Avai_Occ = 'Available'
BEGIN TRAN Update_Patient
UPDATE Patient_Record
SET b_ID = @b_ID
WHERE Admission_Type = 'In Patient'
UPDATE bed
SET Status_Avai_Occ = 'Occupied'
WHERE (b_ID = @b_ID)
COMMIT TRAN Update_Patient
注意:3rd语句将每次将
Patient\u record
表中的每个住院患者
记录更新为相同的床位id。换句话说,每次新患者入院时,每个患者都将被重新分配到下一张可用的床上。那将是一张非常拥挤的床。我想你之所以觉得这很难,是因为你的设计有缺陷,但没有足够的信息来纠正这一点。我不确定您要为哪位患者提供床位,在下面的示例中,我使用了@PatientIdToGiveBed
来指定您将为所有“住院患者”提供同一张床。您可能需要修改此选项,以选择第一个“住院患者”,方式与选择床位相同
事务需要有一个隔离级别可重复读取
,这将阻止两个事务分配同一张床,如果使用默认的读取提交
,两个事务可以选择同一张床。通过这种方式,读取锁定
将保持在所选床上,直到交易完成
您可以将下面的整个语句放入SSMS并运行以测试它
DECLARE @Bed TABLE (
b_ID INT,
Status_Avai_Occ VARCHAR(20)
)
DECLARE @Patient_Record TABLE (
Id INT,
Name VARCHAR(10),
b_ID INT
)
INSERT INTO @Bed VALUES (1, 'Available')
INSERT INTO @Bed VALUES (2, 'Available')
INSERT INTO @Bed VALUES (3, 'Available')
INSERT INTO @Patient_Record VALUES (1, 'Adam', NULL)
INSERT INTO @Patient_Record VALUES (2, 'Ben', NULL)
INSERT INTO @Patient_Record VALUES (3, 'Charles', NULL)
DECLARE @PatientIdToGiveBed INT = 1
SET TRANSACTION ISOLATION LEVEL REPEATABLE READ
BEGIN TRANSACTION
DECLARE @Available_BID INT
SELECT TOP 1 @Available_BID = b_ID FROM @BED WHERE Status_Avai_Occ = 'Available' ORDER BY b_ID
IF @Available_BID IS NULL
BEGIN
Print 'No Beds Available'
COMMIT
RETURN
END
UPDATE @Patient_Record SET b_ID = @Available_BID WHERE Id = @PatientIdToGiveBed
UPDATE @Bed SET Status_Avai_Occ = 'Occupied' WHERE b_ID = @Available_BID
COMMIT
SELECT * FROM @Patient_Record
SELECT * FROM @Bed
如果确实要在一组患者中同时运行此操作,则需要首先匹配床位,然后分配床位,因为在SQL Server中无法同时更新两个表,因此基于集合的选择每次将生成不同的床位ID
-- Set up some temp tables to hold data
DECLARE @availBeds table (num int identity(1,1), b_ID int)
DECLARE @inPatients table (num int identity(1,1), p_ID int)
DECLARE @patientBeds table (p_ID int, b_ID int)
-- Populate table of available beds only, giving them a unique incremental ID
INSERT INTO @availBeds SELECT b_ID FROM Bed WHERE status_avai_occ = 'Available'
-- Populate table of in patients without assigned beds only, giving them a unique incremental ID
INSERT INTO @inPatients SELECT p_ID FROM Patient_Record WHERE admission_type = 'In Patient' AND b_ID IS NULL
-- Join the two tables above based on their incremental ID's,
-- effectively matching up available beds with patients
INSERT INTO @patientBeds
SELECT p.p_ID, b.b_ID FROM @inPatients p
INNER JOIN @availBeds b ON b.num = p.num
-- Update Patient_Record with the new bed ID's
UPDATE p
SET p.b_ID = b.b_ID
FROM Patient_Record p
INNER JOIN @patientBeds b ON p.p_ID = b.p_ID
-- Set the Beds to Occupied
UPDATE Bed SET status_avai_occ = 'Occupied' WHERE b_ID IN (SELECT b_ID FROM @patientBeds)
我认为这是一个基于集合的操作,将不同的床位分配给所有住院患者,如果你将其包装在一个事务中,那么整个过程要么全部完成,要么全部撤销RDBMS@DavidHedlund啊,好吧-我会让OP澄清这一点并调整。谢谢。我的问题和大卫提到的一样。我想为住院患者分配不同的“可用”床位,这意味着每次分配“可用”床位后,我想立即将状态更改为“已占用”这样我就不会一直为所有的病人分配同一张床了…如果问题让人困惑,很抱歉…请帮我解决这个问题…谢谢advance@Gayu-Patient_Record表是否有入院类型为“In Patient”的条目?我尝试了此查询,但我的Patient_记录没有更新。只有床头柜更新了:(请帮忙
-- Set up some temp tables to hold data
DECLARE @availBeds table (num int identity(1,1), b_ID int)
DECLARE @inPatients table (num int identity(1,1), p_ID int)
DECLARE @patientBeds table (p_ID int, b_ID int)
-- Populate table of available beds only, giving them a unique incremental ID
INSERT INTO @availBeds SELECT b_ID FROM Bed WHERE status_avai_occ = 'Available'
-- Populate table of in patients without assigned beds only, giving them a unique incremental ID
INSERT INTO @inPatients SELECT p_ID FROM Patient_Record WHERE admission_type = 'In Patient' AND b_ID IS NULL
-- Join the two tables above based on their incremental ID's,
-- effectively matching up available beds with patients
INSERT INTO @patientBeds
SELECT p.p_ID, b.b_ID FROM @inPatients p
INNER JOIN @availBeds b ON b.num = p.num
-- Update Patient_Record with the new bed ID's
UPDATE p
SET p.b_ID = b.b_ID
FROM Patient_Record p
INNER JOIN @patientBeds b ON p.p_ID = b.p_ID
-- Set the Beds to Occupied
UPDATE Bed SET status_avai_occ = 'Occupied' WHERE b_ID IN (SELECT b_ID FROM @patientBeds)
Begin Tran
update Patient_Record
set b_ID = b.b_ID from bed b where b.Status_Avai_Occ = 'Available'
and Patient_Record.Admission_Type = 'In Patient'
Update bed set Status_Avai_Occ='Occupied' where b_ID in (select b_ID from Patient_Record where Patient_Record.Admission_Type = 'In Patient')
Commit Tran