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What does mysql error 1025 (HY000): Error on rename of './foo' (errorno: 150) mean?
...
You usually get this error if your tables use the InnoDB engine. In that case you would have to drop the foreign key, and then do the alter table and drop the column.
But the tricky part is that you can't drop the foreign key using...
How to sign an android apk file
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https://developer.android.com/studio/publish/app-signing.html
Okay, a small overview without reference or eclipse around, so leave some space for errors, but it works like this
Open your project in eclipse
Press right-mouse - > tools (android tools?) - > export signed application (apk?)
G...
Easy idiomatic way to define Ordering for a simple case class
...[...] to Ordered[TupleN[...]] provided an implicit Ordering[TN] exists for all elements T1, ..., TN of the tuple, which should always be the case because it makes no sense to sort on a data type with no Ordering.
The implicit ordering for Tuples is your go-to for any sorting scenario involving a co...
Reload an iframe with jQuery
...tion() {
document.location.reload();
});
and you are good to go with all browsers.
Reload an iframe with HTML (no Java Script req.)
It have more simpler solution: which works without javaScript in (FF, Webkit)
just make an anchor inSide your iframe
<a href="#" target="_SELF">Refre...
Python concatenate text files
...new file. I could open each file by f = open(...) , read line by line by calling f.readline() , and write each line into that new file. It doesn't seem very "elegant" to me, especially the part where I have to read//write line by line.
...
Convert a float64 to an int in Go
...problem in Go that can be unexpected (at least if you come from Java): "In all non-constant conversions involving floating-point or complex values, if the result type cannot represent the value the conversion succeeds but the result value is implementation-dependent." (golang.org/ref/spec#Conversion...
How to replace multiple strings in a file using PowerShell
... PowerShell to continue parsing the expression on the next line:
$original_file = 'path\filename.abc'
$destination_file = 'path\filename.abc.new'
(Get-Content $original_file) | Foreach-Object {
$_ -replace 'something1', 'something1aa' `
-replace 'something2', 'something2bb' `
-re...
Converting NSString to NSDate (and back again)
...String = @"01-02-2010";
NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];
[dateFormatter setDateFormat:@"dd-MM-yyyy"];
NSDate *dateFromString = [dateFormatter dateFromString:dateString];
NSDate convert to NSString:
NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];
[d...
C++ convert hex string to signed integer
...>> x;
// output it as a signed type
std::cout << static_cast<int>(x) << std::endl;
}
In the new C++11 standard, there are a few new utility functions which you can make use of! specifically, there is a family of "string to number" functions (http://en.cppreference.c...
Displaying better error message than “No JSON object could be decoded”
... also up on PYPI: https://pypi.python.org/pypi/rson/0.9 so you can use easy_install or pip to get it.
for the example given by tom:
>>> rson.loads('[1,2,]')
...
rson.base.tokenizer.RSONDecodeError: Unexpected trailing comma: line 1, column 6, text ']'
RSON is a designed to be a superset...