我想在teradata中迁移以下查询。我更新了表中的一些行,并在sql中编写了这个查询。现在,我想在teradata中的脚本下面迁移。我听说我们需要使用volatile表来选择数据然后更新。我是否必须首先创建易失性表然后更新?
UPDATE gam
SET gam.DeviceActiveInSIGMA = 1,
gam.DeviceInSIGMA =1,
gam.AccountServiceInSIGMA =1,
gam.AccountInSIGMA =1,
gam.PKG_TYPE = 'VOICE',
gam.MACType = 'Voice'
FROM Staging.AllAccountDevices gam
WITH (INDEX (ix_MAC_UniqueID))
INNER JOIN dbo.TBL_SIGMA_VOIP_EQUIPMENT dvc
ON gam.MACAddr = dvc.MTA_MAC
INNER JOIN dbo.TBL_SIGMA_SUB sac
ON dvc.SUB_ID = sac.SUB_ID
AND gam.AccountNumber = sac.Account_Number
LEFT OUTER JOIN HSIRECON.DBO.NEXTGEN_ACTIVE_SPAS nas
ON SUBSTRING(gam.AccountNumber,1,6) = nas.ACCOUNT_START
WHERE nas.ACCOUNT_START is NULL
AND gam.DeviceActiveInSIGMA = 0
AND dvc.STATUS IN ('active','change_in_progress')
答案 0 :(得分:1)
您不需要使用Volatile Table,而是使用派生表,因为Teradata不支持更新中的外部联接。
与此类似:
UPDATE gam
FROM Staging.AllAccountDevices AS gam,
(
SELECT * FROM Staging.AllAccountDevices gam
INNER JOIN dbo.TBL_SIGMA_VOIP_EQUIPMENT dvc
ON gam.MACAddr = dvc.MTA_MAC
INNER JOIN dbo.TBL_SIGMA_SUB sac
ON dvc.SUB_ID = sac.SUB_ID
AND gam.AccountNumber = sac.Account_Number
LEFT OUTER JOIN HSIRECON.DBO.NEXTGEN_ACTIVE_SPAS nas
ON Substr(gam.AccountNumber,1,6) = nas.ACCOUNT_START
WHERE nas.ACCOUNT_START IS NULL
AND gam.DeviceActiveInSIGMA = 0
AND dvc.STATUS IN ('active','change_in_progress')
) AS dt
SET DeviceActiveInSIGMA = 1,
DeviceInSIGMA =1,
AccountServiceInSIGMA =1,
AccountInSIGMA =1,
PKG_TYPE = 'VOICE',
MACType = 'Voice'
WHERE gam.pk = dt.pk -- must be the Primary Key columns(s) of Staging.AllAccountDevices
AND gam.DeviceActiveInSIGMA = 0
顺便说一句,原始查询是为SQL Server而不是Oracle编写的。