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MySQL, Check if a column exists in a table with SQL
I am trying to write a query that will check if a specific table in MySQL has a specific column, and if not — create it. Otherwise do nothing. This is really an easy procedure in any enterprise-class database, yet MySQL seems to be an exception.
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NoSql vs Relational database
Recently NoSQL has gained immense popularity.
9 Answers
9
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Where is my .vimrc file?
...ettings. The problem I am having is that I cannot find my .vimrc file, and it is not in the standard /home/user/.vimrc location. How might I find this file?
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When should I use semicolons in SQL Server?
...QL Server Management Studio I have noticed that some statements are ended with a semicolon.
13 Answers
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Load a UIView from nib in Swift
...and a class named SomeView (used the same name for
convenience and readability). I based both on a UIView.
In the XIB, I changed the "File's Owner" class to SomeView (in the identity inspector).
I created a UIView outlet in SomeView.swift, linking it to the top level view in the XIB file (named it "...
Spinlock versus Semaphore
...ossible implementation of a lock, namely one that is implemented by busy waiting ("spinning"). A semaphore is a generalization of a lock (or, the other way around, a lock is a special case of a semaphore). Usually, but not necessarily, spinlocks are only valid within one process whereas semaphores c...
Which is more efficient, a for-each loop, or an iterator?
...on to read all of the values, then there is no difference between using an iterator or the new for loop syntax, as the new syntax just uses the iterator underwater.
If however, you mean by loop the old "c-style" loop:
for(int i=0; i<list.size(); i++) {
Object o = list.get(i);
}
Then the ne...
Peak detection in a 2D array
...m filter. Here is the result on your first dataset of 4 paws:
I also ran it on the second dataset of 9 paws and it worked as well.
Here is how you do it:
import numpy as np
from scipy.ndimage.filters import maximum_filter
from scipy.ndimage.morphology import generate_binary_structure, binary_ero...
How to convert SecureString to System.String?
...ions about unsecuring your SecureString by creating a System.String out of it aside , how can it be done?
11 Answers
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Use 'import module' or 'from module import'?
I've tried to find a comprehensive guide on whether it is best to use import module or from module import . I've just started with Python and I'm trying to start off with best practices in mind.
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