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LEFT JOIN only first row
... Thanks for your fast response. This was not the exact answer, but totally got me on the right way. I always tried to join both on the same level instead of making the one depended from the other. Thank you very much for leading me on the right track. Edited the first post
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Error: Jump to case label
...code, if foo equals 1, everything is ok, but if it equals 2, we'll accidentally use the i variable which does exist but probably contains garbage.
switch(foo) {
case 1:
int i = 42; // i exists all the way to the end of the switch
dostuff(i);
break;
case 2:
dostuff(i*2); // i is ...
Is using a lot of static methods a bad thing?
I tend to declare as static all the methods in a class when that class doesn't require to keep track of internal states. For example, if I need to transform A into B and don't rely on some internal state C that may vary, I create a static transform. If there is an internal state C that I want to be ...
How do I test for an empty JavaScript object?
...do you post answer including jQuery if the question is not about jQuery at all?
– Eru
Oct 1 '12 at 14:10
48
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Starting python debugger automatically on error
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You can use traceback.print_exc to print the exceptions traceback. Then use sys.exc_info to extract the traceback and finally call pdb.post_mortem with that traceback
import pdb, traceback, sys
def bombs():
a = []
print a[0]
if __name__ == '...
jQuery vs document.querySelectorAll
...ve the same result with document.querySelector or document.querySelectorAll , which are supported in Internet Explorer 8 and above.
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Java “lambda expressions not supported at this language level”
...: android { compileOptions { sourceCompatibility JavaVersion.VERSION_1_8 targetCompatibility JavaVersion.VERSION_1_8 } }
– BaDo
Sep 25 '15 at 2:30
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Initializing a static std::map in C++
... Every time I see something like that done with C++, I think of all the horrendous template code that must be behind it. Good example!
– Greg Hewgill
Sep 26 '08 at 10:22
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Maven fails to find local artifact
Occasionally maven complains that a particular dependency, which is built and packaged locally, cannot be found in the local repository while building another project that has it as a dependency. We get an error like:
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Adding :default => true to boolean in existing Rails column
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change_column is a method of ActiveRecord::Migration, so you can't call it like that in the console.
If you want to add a default value for this column, create a new migration:
rails g migration add_default_value_to_show_attribute
Then in the migration created:
# That's the more generic way t...