uniqueidentifier

问题 I am trying to insert data from one table into another table. Table1 doesn't have a uniqueidentifier, but Table2 does. I have tried to insert using NEWID() , but I get a syntax error. Can someone please tell me what I am doing wrong? INSERT INTO Table2 (NEWID(), [Item Description], [Item Cost]) SELECT Description, Cost FROM Table1 WHERE Id = '1' 回答1: In case Table2 is not yet created you can use this query: SELECT NEWID() AS [ID] ,Description AS [Item Description] ,Cost AS [Item Cost] INTO

问题 I am looking for a way in C# to have a persistent (across when end-users unplug a hub/restart their computer) identifier for USB slots, more specifically, SD card readers. Drive letters are not always assigned to the same slot, but I need a way to identify Slot A physically; as once I can identify it, I can make the connections to a drive letter. So my question(s): Is this possible? If so, how would I go about getting these identifiers? 回答1: WMI class Win32_USBHub. ManagementObjectSearcher

问题 In order to investigate whether Hibernate's behavior is different than NHibernate's for a particular usage scenario, I began writing a Java SE & Hibernate port of the relevant parts of my NHibernate-based application, but encountered a problem with obtaining an entity where the corresponding SQL Server 2008 R2 Express table uses a uniqueidentifier for the primary key. Here's the mapping file: <!-- User.hbm.xml --> <?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE hibernate-mapping PUBLIC "-/

问题 Since few days I am trying to get MAC Adress from my Windows Phone device withouse success. I am trying to get UNIQUE ID for my Phone, Tablet etc. I`ve found HardwareToken class and the code below HardwareToken token = HardwareIdentification.GetPackageSpecificToken(null); IBuffer hardwareId = token.Id; HashAlgorithmProvider hasher = HashAlgorithmProvider.OpenAlgorithm("MD5"); IBuffer hashed = hasher.HashData(hardwareId); string hashedString = CryptographicBuffer.EncodeToHexString(hashed);

问题 I am looking to use numpy.unique to obtain the reverse unique indexes of two columns of a pandas.DataFrame . I know how to use it on one column: u, rev = numpy.unique(df[col], return_inverse=True) But I want to use it on multiple columns. For example, if the df looks like: 0 1 0 1 1 1 1 2 2 2 1 3 2 1 4 3 1 then I would like to get the reverse indexes: [0,1,2,2,3] 回答1: Approach #1 Here's one NumPy approach converting each row to a scalar each thinking of each row as one indexing tuple on a two

问题 I try to understand the receipt information obtained from iTunes server, but could not find relevant documentation. Particularly, what's the difference among unique_identifier , unique_vendor_identifier , original_transaction_id (which is claimed, in a WWDC'12 session, to be a de facto customer id) and [[[UIDevice currentDevice] identifierForVendor] UUIDString] ? {"receipt": {"original_purchase_date_pst":"...", "purchase_date_ms":"...", "unique_identifier":"...", "original_transaction_id":"..

问题 I require the list of fixed properties of android.os.Build class. I've obtained the list from here I bold those that I know are fixed. By fix I mean no change by firmware update, reset factory, ... android.os.Build.VERSION.RELEASE //The current development codename, or the string "REL" if this is a release build. android.os.Build.BOARD //The name of the underlying board, like "goldfish". android.os.Build.BOOTLOADER // The system bootloader version number. android.os.Build.BRAND //The brand (e

问题 I have a practical question when I have two (or more) data frames and want to assign unique IDs for each matching observation within each and across both datasets e.g.: #1. Create dataframe df1: a1 <- c(1, 1, 1, 1, 2, 2, 2, 2, 1, 1) b1 <- c(1, 5, 3, 2, 3, 4, 5, 1, 5, 2) c1 <- c("white", "red", "black", "white", "red", "white", "black", "silver", "red", "green") df1 <- data.frame(a1, b1, c1) df1 a1 b1 c1 1 1 1 white 2 1 5 red 3 1 3 black 4 1 2 white 5 2 3 red 6 2 4 white 7 2 5 black 8 2 1

问题 We use uniqueidentifier for every record within a very large database. For business reasons we need to ensure that the uniqueidentifier is never used more than once, but for performance reasons we have a bigint as the primary key . What is the fastest way to test the existence of a uniqueidentifer in a Sql server table? 回答1: ** < 0.05ms to validate a uniqueidentifier from 100,000,000 rows on a single Standard S0 Sql Azure instance. ** DISCLAIMER: The following aproach may require tweaking to

问题 I want to be able to assign a unique name to each PC in a WAN (either in the hostname or in a local file) and somehow allow the browser to pick this information up . The rationale is that I can later trace that "transaction X was carried out on terminal A", which I then know that it is on building B, floor C, room D and so on. Why we need this, it's another topic. Just say we do need this kind of identification for good reason. So far we've used a custom plugin (.dll + .xpi) that would read a