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MySQL Cannot Add Foreign Key Constraint
...onstraints to my database as a project requirement and it worked the first time or two on different tables, but I have two tables on which I get an error when trying to add the Foreign Key Constraints.
The error message that I get is:
...
Getting a random value from a JavaScript array
...
Say you want to choose a random item that is different from the last time (not really random, but still a common requirement)...
Building upon the answer by @Markus, we can add another prototype function:
Array.prototype.randomDiffElement = function(last) {
if (this.length == 0) {
r...
Combining two Series into a DataFrame in pandas
...er doing the concat once pd.concat([list_of_dataframes]) vs concating many times new_df = pd.DataFrame(); for df in list_of_dsf: new_df = pd.concat([new_df, df]) or similar.
– Andy Hayden
Oct 14 '15 at 22:07
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How to convert a string to lower or upper case in Ruby
...bout it after I had answered it, but I'll give you the cred for taking the time to answer it anyway. Thanks!
– Heat Miser
Jun 20 '09 at 0:30
4
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How to convert jsonString to JSONObject in Java
...on-benchmark It clearly shows jackson faster than anything else and 5 to 6 times faster than org.json.
– fabien
Jun 27 '16 at 20:47
5
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How to determine the screen width in terms of dp or dip at runtime in Android?
...code the layout of the android widgets using dip/dp (in java files). At runtime if I code,
int pixel=this.getWindowManager().getDefaultDisplay().getWidth() ;
...
Making your .NET language step correctly in the debugger
...VS (2008+) can-to run as a non-admin
Do any symbols load at all the second time around? You might test by breaking in (through exception or call System.Diagnostic.Debugger.Break())
Assuming that symbols load, is there a repro that you could send us?
The likely difference is that the symbol format fo...
get the latest fragment in backstack
... this working solution:
Add this utility method that will be used several times below to get the number of fragments in your backstack:
protected int getFragmentCount() {
return getSupportFragmentManager().getBackStackEntryCount();
}
Then, when you add/replace your fragment using FragmentTra...
How to change title of Activity in Android?
...upportActionBar() and getActionBar() also nulls i cant set the title in runtime.
– Ninja Coding
Jan 26 '16 at 17:30
1
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“/usr/bin/ld: cannot find -lz”
... is how the apt packaging manager knows to resolve the python-lxml compile-time virtualenv package dependency on libz-dev via zlib1g-dev.
– TrinitronX
Jul 5 at 0:30
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