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SQLAlchemy default DateTime
...
DateTime doesn't have a default key as an input. The default key should be an input to the Column function. Try this:
import datetime
from sqlalchemy import Column, Integer, DateTime
from sqlalchemy.ext.declarative import declarative...
Setting variable to NULL after free
...ngling pointer is accessed after it is freed, you may read or overwrite random memory. If a null pointer is accessed, you get an immediate crash on most systems, telling you right away what the error is.
For local variables, it may be a little bit pointless if it is "obvious" that the pointer isn't...
Warning: “format not a string literal and no format arguments”
...
Are you nesting your brackets correctly? I don't think NSLog() likes taking only one argument, which is what you're passing it. Also, it already does the formatting for you. Why not just do this?
NSLog(@"%@ %@, %@",
errorMsgFormat,
error,
[error userInfo]...
Start two instances of IntelliJ IDE
Well my question is pretty simple, how do I start two instances of IntelliJ (community edition).
When I have one instance started and I try to start another one, all that happens is that my started instance gets focus.
...
Android Spinner: Get the selected item change event
...us answers are not correct. They work for other widgets and views, but the documentation for the Spinner widget clearly states:
A spinner does not support item click
events. Calling this method will raise
an exception.
Better use OnItemSelectedListener() instead:
spinner.setOnItemSelecte...
Calculate size of Object in Java [duplicate]
...omparing sizes of data structures) and it seems like there is no method to do this in Java. Supposedly, C/C++ has sizeOf() method, but this is nonexistant in Java. I tried recording the free memory in the JVM with Runtime.getRuntime().freeMemory() before and after creating the object and then re...
How to iterate over associative arrays in Bash
...u can iterate over the key/value pairs like this:
for i in "${!array[@]}"
do
echo "key : $i"
echo "value: ${array[$i]}"
done
Note the use of quotes around the variable in the for statement (plus the use of @ instead of *). This is necessary in case any keys include spaces.
The confusion in ...
Execute the setInterval function without delay the first time
...elf for subsequent calls using setTimeout instead:
function foo() {
// do stuff
// ...
// and schedule a repeat
setTimeout(foo, delay);
}
// start the cycle
foo();
This guarantees that there is at least an interval of delay between calls. It also makes it easier to cancel the loop ...
Postgresql: password authentication failed for user “postgres”
...led. I did it before a couple of times without this problem. What should I do? And what happens?
18 Answers
...
Fastest way to determine if an integer's square root is an integer
...programming language (C/C++). Your results may vary, especially because I don't know how the Java factor will play out.
My approach is threefold:
First, filter out obvious answers. This includes negative numbers and looking at the last 4 bits. (I found looking at the last six didn't help.) I ...