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ALTER TABLE to add a composite primary key
...er table parent drop column id;
ERROR 1025 (HY000): Error on rename of
'./test/#sql-a04_b' to './test/parent' (errno: 150).
If you want to drop a primary key that's being referenced by another table, you will have to drop the foreign key in that other table first. You can recreate that foreign k...
Why is the Java main method static?
...guage Specification
Check out Chapter 12 Execution - Section 12.1.4 Invoke Test.main:
Finally, after completion of the initialization for class Test (during which other consequential loading, linking, and initializing may have occurred), the method main of Test is invoked.
The method main must be d...
Returning value from called function in a shell script
...ere's how to do each of those options:
1. Echo strings
lockdir="somedir"
testlock(){
retval=""
if mkdir "$lockdir"
then # Directory did not exist, but it was created successfully
echo >&2 "successfully acquired lock: $lockdir"
retval="true"
else
ec...
What is the “hasClass” function with plain JavaScript?
...Query's implementation is better and more reliable. For example: /\bbig\b/.test('big-text') returns true instead of expected false.
– Stano
Jun 18 '13 at 18:43
...
How to remove all breakpoints in one step in Google Chrome?
... answered Apr 17 at 13:13
test666test666
2111 bronze badge
add a...
https connection using CURL from command line
...ld and facing a problem while connecting to a server.
Basically, I need to test connectivity over https from one machine to another machine.
I have a URL to which I need to connect from Machine A (a linux machine)
I tried this on command prompt
...
How can I maintain fragment state when added to the back stack?
...ash. Version 2 removes _rootView in onDestroyView(), as dell116 suggested. Tested on Android 4.0.3, 4.4.4, 5.1.0.
Version 2
public class FragmentA extends Fragment {
View _rootView;
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState...
Hide Utility Class Constructor : Utility classes should not have a public or default constructor
...
Indeed, how are you supposed to test/cover such 'unreachable' code?
– dokaspar
Jun 11 '15 at 20:25
11
...
Return None if Dictionary key is not available
...clue on how to extend this to support any depth? I mean making foo['bar']['test']['sss'] to return None instead of exception, After one depth it start giving TypeError instead of KeyError
– nehem
Nov 10 '15 at 1:40
...
How do I prompt for Yes/No/Cancel input in a Linux shell script?
...cho Yes
else
echo No
fi
(Thanks to Adam Katz's comment: Replaced the test above with one that is more portable and avoids one fork:)
POSIX, but single key feature
But if you don't want the user to have to hit Return, you could write:
(Edited: As @JonathanLeffler rightly suggest, saving stty...