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Check if a temporary table exists and delete if it exists before creating a temporary table
...ollowing code to check if the temporary table exists and drop the table if it exists before creating again. It works fine as long as I don't change the columns. If I add a column later, it will give an error saying "invalid column". Please let me know what I am doing wrong.
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Are PHP include paths relative to the file or the calling code?
...tion to the location of B.PHP, or to the location of A.PHP? That is, does it matter which file the include is called from, or only what the current working directory is- and what determines the current working directory?
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Is it a bad practice to use an if-statement without curly braces? [closed]
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The problem with the first version is that if you go back and add a second statement to the if or else clauses without remembering to add the curly braces, your code will break in unexpected and amusing ways.
Maintainability-wise, it's a...
How to check if a string is a valid date
I have a string: "31-02-2010" and want to check whether or not it is a valid date.
What is the best way to do it?
14 Answ...
How to write WinForms code that auto-scales to system font and dpi settings?
...t there that say "WinForms doesn't auto-scale to DPI/font settings well; switch to WPF." However, I think that is based on .NET 1.1; it appears they actually did a pretty good job of implementing auto-scaling in .NET 2.0. At least based on our research and testing so far. However, if some of you out...
What is the difference between pip and conda?
...ager for python packages. However, I saw the installation on IPython's website use conda to install IPython.
12 Answers
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What is the difference between null and undefined in JavaScript?
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alert(typeof TestVar); //shows undefined
null is an assignment value. It can be assigned to a variable as a representation of no value:
var TestVar = null;
alert(TestVar); //shows null
alert(typeof TestVar); //shows object
From the preceding examples, it is clear that undefined and null are ...
Private vs Public in Cache-Control
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The only difference is that with Private you are not allowing proxies to cache the data that travels through them. In the end, it all boils down to the data contained in the pages/files you are sending.
For example, your ISP could have an invisible prox...
Ineligible Devices section appeared in Xcode 6.x.x
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With the release of Xcode 6.3.1, check first the Update 5
Verify that "iOS Deployment Target" is <= the version of your iDevice.
You find this option in "Build Settings" tab when you click on a target of your projec...
SQLAlchemy: cascade delete
I must be missing something trivial with SQLAlchemy's cascade options because I cannot get a simple cascade delete to operate correctly -- if a parent element is a deleted, the children persist, with null foreign keys.
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