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MySQL JOIN the most recent row only?
I have a table customer that stores a customer_id, email and reference. There is an additional table customer_data that stores a historical record of the changes made to the customer, i.e. when there's a change made a new row is inserted.
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Quickest way to convert a base 10 number to any base in .NET?
I have and old(ish) C# method I wrote that takes a number and converts it to any base:
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Is there any pythonic way to combine two dicts (adding values for keys that appear in both)?
For example I have two dicts:
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Why is address zero used for the null pointer?
In C (or C++ for that matter), pointers are special if they have the value zero: I am adviced to set pointers to zero after freeing their memory, because it means freeing the pointer again isn't dangerous; when I call malloc it returns a pointer with the value zero if it can't get me memory; I use ...
Replace all 0 values to NA
I have a dataframe with some numeric columns. Some row has a 0 value which should be considered as null in statistical analysis. What is the fastest way to replace all the 0 value to NULL in R?
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Does VBA have Dictionary Structure?
Does VBA have dictionary structure? Like keyvalue array?
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What is the $? (dollar question mark) variable in shell scripting? [duplicate]
I'm trying to learn shell scripting, and I need to understand someone else's code. What is the $? variable hold? I can't Google search the answer because they block punctuation characters.
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Pandas: Looking up the list of sheets in an excel file
The new version of Pandas uses the following interface to load Excel files:
6 Answers
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Code Golf - π day
Guidelines for code-golf on SO
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How to use custom packages
I'm trying to create and use a custom package in Go. It's probably something very obvious but I cannot find much information about this. Basically, I have these two files in the same folder:
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