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PostgreSQL: Drop PostgreSQL database through command line [closed]
...e'
– leszek.hanusz
Jan 24 '15 at 12:06
\l to see all the databases you have.
– Sandip Subedi
...
Declaring variables inside or outside of a loop
....Test extends java.lang.Object{
public inside.Test();
Code:
0: aload_0
1: invokespecial #1; //Method java/lang/Object."<init>":()V
4: return
public static void main(java.lang.String[]);
Code:
0: invokestatic #2; //Method java/lang/System.currentTimeMillis:()J
3...
What is the difference between join and merge in Pandas?
...andas as pd
left = pd.DataFrame({'key': ['foo', 'bar'], 'val': [1, 2]}).set_index('key')
right = pd.DataFrame({'key': ['foo', 'bar'], 'val': [4, 5]}).set_index('key')
left.join(right, lsuffix='_l', rsuffix='_r')
val_l val_r
key
foo 1 4
bar 2 5
The same functi...
How do I print the elements of a C++ vector in GDB?
...td::vector<int> called myVector, do the following:
print *(myVector._M_impl._M_start)@myVector.size()
To print only the first N elements, do:
print *(myVector._M_impl._M_start)@N
Explanation
This is probably heavily dependent on your compiler version, but for GCC 4.1.2, the pointer to t...
How to check if a python module exists without importing it
...mport can find something in python2, using imp
import imp
try:
imp.find_module('eggs')
found = True
except ImportError:
found = False
To find dotted imports, you need to do more:
import imp
try:
spam_info = imp.find_module('spam')
spam = imp.load_module('spam', *spam_info)
i...
What's the difference between dynamic (C# 4) and var?
... {
[CompilerGenerated]
private static class <Main>o__SiteContainer0
{
public static CallSite<Action<CallSite, object>> <>p__Site1;
}
private static void Main(string[] args)
{
Junk a = new Junk(); /...
Is there a foreach loop in Go?
...
https://golang.org/ref/spec#For_range
A "for" statement with a "range" clause iterates through all entries
of an array, slice, string or map, or values received on a channel.
For each entry it assigns iteration values to corresponding iteration
v...
What is a singleton in C#?
...Prevent outside instantiation
}
private static readonly Singleton _singleton = new Singleton();
public static Singleton GetSingleton()
{
return _singleton;
}
}
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...
How can I output leading zeros in Ruby?
...counter is known (e.g., n = 3 for counters 1..876), you can do
str = "file_" + i.to_s.rjust(n, "0")
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...
Do I need to disable NSLog before release Application?
...Debug configuration add a value to "Preprocessor Macros" value like:
DEBUG_MODE=1
Make sure you only do this for the Debug configuration and not for Beta or Release versions. Then in a common header file you can do something like:
#ifdef DEBUG_MODE
#define DLog( s, ... ) NSLog( @"<%p %@:(%d)&...