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Insert Update trigger how to determine if insert or update
...ble A's column (say Col1). How would I go around writing it so that I can handle both Update and Insert cases. How would I determine if the trigger is executed for an update or insert.
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Difference between val() and text()
What the difference between jQuery's functions val() and text() ?
4 Answers
4
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Do HTML WebSockets maintain an open connection for each client? Does this scale?
... line of communication with the server. I'm just wondering how that scales and how many open WebSocket connections a server can handle. Maybe leaving those connections open isn't a problem in reality, but it feels like it is.
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Can't subtract offset-naive and offset-aware datetimes
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naive datetime objects are inherently ambiguous and therefore they should be avoided. It is easy to add tzinfo instead
– jfs
Sep 4 '14 at 9:39
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ggplot2 legend to bottom and horizontal
How can I move a ggplot2 legend to the bottom of the plot and turn it horizontally?
2 Answers
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C++ : why bool is 8 bits long?
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Yes, it's a hardware choice, and if the hardware allows for it, the size of a bool could change. But the OP asked why a bool is 8 bits wide, and on systems where that is the case, it is generally because the CPU is only able to address 8-bit bytes.
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Why can't I define a static method in a Java interface?
...ic interface methods were initially considered as a small language change, and then there was an official proposal to add them in Java 7, but it was later dropped due to unforeseen complications.
Finally, Java 8 introduced static interface methods, as well as override-able instance methods with a d...
How can I style even and odd elements?
Is it possible to use CSS pseudo-classes to select even and odd instances of list items?
9 Answers
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is_null($x) vs $x === null in PHP [duplicate]
PHP has two (that I know of, and three if you count isset() ) methods to determine if a value is null: is_null() and === null . I have heard, but not confirmed, that === null is faster, but in a code review someone strongly suggested that I use is_null() instead as it is specifically design...
Convert an image to grayscale in HTML/CSS
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Support for CSS filters has landed in Webkit. So we now have a cross-browser solution.
img {
filter: gray; /* IE6-9 */
-webkit-filter: grayscale(1); /* Google Chrome, Safari 6+ & Opera 15+ */
filter: grayscale(1); /* Microsoft Edge and...