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Is there a performance difference between CTE , Sub-Query, Temporary Table or Table Variable?
In this excellent SO question , differences between CTE and sub-queries were discussed.
4 Answers
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Scatter plot and Color mapping in Python
I have a range of points x and y stored in numpy arrays.
Those represent x(t) and y(t) where t=0...T-1
3 Answers
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How can prepared statements protect from SQL injection attacks?
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The idea is very simple - the query and the data are sent to the database server separately.
That's all.
The root of the SQL injection problem is in the mixing of the code and the data.
In fact, our SQL query is a legitimate program.
And we are creating s...
In what order are Panels the most efficient in terms of render time and performance?
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I think it is more concise and understandable to describe the performance characteristics of each panel than it is to try to give an absolute relative performance comparison.
WPF makes two passes when rendering content: Measure and Arrange. Each pane...
Event system in Python
...raries to choose from, using very different terminology (events, signals, handlers, method dispatch, hooks, ...).
I'm trying to keep an overview of the above packages, plus the techniques mentioned in the answers here.
First, some terminology...
Observer pattern
The most basic style of event system ...
What is the formal difference in Scala between braces and parentheses, and when should they be used?
...rmal difference between passing arguments to functions in parentheses () and in braces {} ?
9 Answers
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What is the difference between And and AndAlso in VB.NET?
In VB.NET, what is the difference between And and AndAlso ? Which should I use?
11 Answers
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Failed to enable constraints. One or more rows contain values violating non-null, unique, or foreign
I make an outer join and executed successfully in the informix database but I get the following exception in my code:
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How do you check whether a number is divisible by another number (Python)?
...le of 5. The way I thought I'd do this would be to divide the number by 3, and if the result is an integer then it would be a multiple of 3. Same with 5.
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How to make git-diff and git log ignore new and deleted files?
...ometimes there's a couple of changed files together with some new, deleted and/or renamed files. When doing git diff or git-log I'd like to omit them, so I can better spot the modifications.
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