使用 OUTPUT 条款：

CREATE TABLE #temp (CustomerId <datatype> );

INSERT INTO [dbo].[BudCustomers]
           ([LegalName]
           ,[EffectiveDate]
           ,[LawsonCustomerNumber]
           ,[ChangeReason]
           ,[ImportedRecord]
           ,[VersionID]
           ,[StatusID]
           ,[CreatedDate]
           ,[CreatedUserID]
           ,[LastModifiedDate]
           ,[LastModifiedUserID]
           ,[CustomerGroupID])
OUTPUT inserted.CustomerId
INTO #temp
SELECT CustomerName
         ,'1900-01-01 00:00:00.000'
         , CASE 
           WHEN PATINDEX('%[0-9]%', CustomerName) > 0 
            THEN REPLACE(SUBSTRING(CustomerName, PATINDEX('%[0-9]%', CustomerName),
            LEN(CustomerName)), ')', '')  ELSE 0 END
         ,''
         ,1
         ,1
         ,1
         ,GETDATE()
         ,'Import'
         ,GETDATE()
         ,'Import'
         ,NULL
FROM External_Blk_Itm_Contracts
WHERE TerminalName NOT IN (SELECT MBFTERMINALNAME FROM budterminals)

SELECT *
FROM #temp;