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How do you set a default value for a MySQL Datetime column?
... need to ALWAYS specify a value for this column or the value will automatically reset itself to "now()" on update. This means that if you do not want the value to change, your UPDATE statement must contain "[your column name] = [your column name]" (or some other value) or the value will become "now(...
PHP Fatal error: Using $this when not in object context
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@Sarfraz No offense, but it is still wrong. You can call an instance method with ::. It is against E_STRICT, but it does work as long as the method body does not reference the instance scope, e.g. uses $this. Also, self::foo will not point to $this->foo. It references a clas...
Java Serializable Object to Byte Array
...Object);
out.flush();
byte[] yourBytes = bos.toByteArray();
...
} finally {
try {
bos.close();
} catch (IOException ex) {
// ignore close exception
}
}
Create an object from a byte array:
ByteArrayInputStream bis = new ByteArrayInputStream(yourBytes);
ObjectInput in = null;
tr...
Using “like” wildcard in prepared statement
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@Alain: Thank you. Just wondering, does this apply to all RDBMS the world is aware of? Perhaps '%' || ? || '%' as mentioned in 1st comment was better, after all? I don't have the opportunity to experiment right now.
– BalusC
Dec 23 '15 at 2...
How do I intercept a method call in C#?
... like to have tracing functionality i.e. I would like to log every method call (method signature and actual parameter values) and every method exit (just the method signature).
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C/C++ check if one bit is set in, i.e. int variable
...if you want to hide bit manipulation, you can write a macro:
#define CHECK_BIT(var,pos) ((var) & (1<<(pos)))
and use it this way to check the nth bit from the right end:
CHECK_BIT(temp, n - 1)
In C++, you can use std::bitset.
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Is there any overhead to declaring a variable within a loop? (C++)
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Stack space for local variables is usually allocated in function scope. So no stack pointer adjustment happens inside the loop, just assigning 4 to var. Therefore these two snippets have the same overhead.
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OS X Bash, 'watch' command
...ulate the basic functionality with the shell loop:
while :; do clear; your_command; sleep 2; done
That will loop forever, clear the screen, run your command, and wait two seconds - the basic watch your_command implementation.
You can take this a step further and create a watch.sh script that can...
Get Enum from Description attribute [duplicate]
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value.ToString() is expensive, do not call it twice (.. if it matters)...
– nawfal
Jun 11 '13 at 1:26
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Split (explode) pandas dataframe string entry to separate rows
...bine where Apply returns a dataframe of arbitrary size (but consistent for all chunks), and Combine just vstacks the returned DFs?
– Vincent
Oct 2 '12 at 0:22
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