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MySQL - Rows to Columns
I tried to search posts, but I only found solutions for SQL Server/Access. I need a solution in MySQL (5.X).
12 Answers
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How can I force division to be floating point? Division keeps rounding down to 0?
I have two integer values a and b , but I need their ratio in floating point. I know that a < b and I want to calculate a / b , so if I use integer division I'll always get 0 with a remainder of a .
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What is a regular expression for a MAC Address?
In this format:
21 Answers
21
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How to toggle a value in Python
What is the most efficient way to toggle between 0 and 1 ?
17 Answers
17
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How can I convert a DateTime to the number of seconds since 1970?
I'm trying to convert a C# DateTime variable to Unix time, ie, the number of seconds since Jan 1st, 1970. It looks like a DateTime is actually implemented as the number of 'ticks' since Jan 1st, 0001.
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Boolean Field in Oracle
Yesterday I wanted to add a boolean field to an Oracle table. However, there isn't actually a boolean data type in Oracle. Does anyone here know the best way to simulate a boolean? Googling the subject discovered several approaches
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Remove rows with all or some NAs (missing values) in data.frame
I'd like to remove the lines in this data frame that:
16 Answers
16
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How do you add swap to an EC2 instance?
I'm currently running an ec2 micro instance and i've been finding that the instance occasionally runs out of memory.
10 Ans...
Filter rows which contain a certain string
I have to filter a data frame using as criterion those row in which is contained the string RTB .
4 Answers
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Python assigning multiple variables to same value? list behavior
I tried to use multiple assignment as show below to initialize variables, but I got confused by the behavior, I expect to reassign the values list separately, I mean b[0] and c[0] equal 0 as before.
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