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T-SQL: Deleting all duplicate rows but keeping one [duplicate]
I have a table with a very large amount of rows. Duplicates are not allowed but due to a problem with how the rows were created I know there are some duplicates in this table.
I need to eliminate the extra rows from the perspective of the key columns. Some other columns may have slightly different...
What do Clustered and Non clustered index actually mean?
I have a limited exposure to DB and have only used DB as an application programmer. I want to know about Clustered and Non clustered indexes .
I googled and what I found was :
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Simple way to find if two different lists contain exactly the same elements?
What is the simplest way to find if two Lists contain exactly the same elements, in the standard Java libraries?
16 Answer...
C++中智能指针的设计和使用 - C/C++ - 清泛网 - 专注C/C++及内核技术
C++中智能指针的设计和使用 智能指针(smart pointer)是存储指向动态分配（堆）对象指针的类，用于生存期控制，能够确保自动正确的销毁动态分配的对象，防止内存泄露。它的一种通用实现技术是使用引用计 智能指针(smart p...
Reasons for using the set.seed function
Many times I have seen the set.seed function in R, before starting the program. I know it's basically used for the random number generation. Is there any specific need to set this?
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Why does this Java program terminate despite that apparently it shouldn't (and didn't)?
A sensitive operation in my lab today went completely wrong. An actuator on an electron microscope went over its boundary, and after a chain of events I lost $12 million of equipment. I've narrowed down over 40K lines in the faulty module to this:
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NOT IN vs NOT EXISTS
Which of these queries is the faster?
11 Answers
11
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How to Iterate over a Set/HashSet without an Iterator?
How can I iterate over a Set / HashSet without the following?
8 Answers
8
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Does Java 8 provide a good way to repeat a value or function?
In many other languages, eg. Haskell, it is easy to repeat a value or function multiple times, eg. to get a list of 8 copies of the value 1:
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Load data from txt with pandas
I am loading a txt file containig a mix of float and string data. I want to store them in an array where I can access each element. Now I am just doing
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