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Joins are for lazy people?
...0 rows in B, B has only 100 rows, and we want to fetch the first 1000 rows from A with associated rows from B. Joining in the database will result in 20 * 1000 tuples sent across the network. If the join is done in the app server (first fetching the entire B table into memory), a mere 100 + 1000 row...
Tools for JPEG optimization? [closed]
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I'm going for this one. It reduces my background image from 62 kB to 49 kB in progressive mode. Another image (27 kB) was reduced to 23 kB. That's 15-20% savings without loss in quality!
– chris166
Jun 12 '09 at 13:51
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Apache Spark: map vs mapPartitions?
...only once. Even if the RDD is cached in RAM, that saves a lot of overhead from type conversion.
– Bob
Mar 27 '15 at 4:58
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HTML5 dragleave fired when hovering a child element
...ragEnterTarget is set, I ignore further dragenter events, because they are from children. In all dragleave events I check dragEnterTarget === event.target. If this is false the event will be ignored as it was fired by a child. If this is true I reset dragEnterTarget to undefined.
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Best programming aids for a quadriplegic programmer
... Please don't let this being check as the "answer" stop you from posting more possibilities. I'll also add that (gasp) I've been a vi (and now vim) guy since 1980, so I'll have to be creating a "vi macro set" to complement the work that Andre has already done, and probably also a Note...
How to get the process ID to kill a nohup process?
...n find the PID later on by ps -ef | grep "command name" and locate the PID from there. Note that nohup keyword/command itself does not appear in the ps output for the command in question.
If you use a script, you could do something like this in the script:
nohup my_command > my.log 2>&1 &a...
Segmentation fault on large array sizes
...at the disasseble you will see the size of your local variables subtracted from the stack pointer. When you call malloc or calloc or any of the memory fuctions the fuctions go and find blocks of memory large enough to sataisfy your reqest.
– rerun
Dec 4 '09 at...
How to convert date to timestamp in PHP?
How do I get timestamp from e.g. 22-09-2008 ?
19 Answers
19
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Best way to run scheduled tasks [closed]
...need to be scheduled) for a website are kept within the website and called from a special page. I then wrote a simple Windows service which calls this page every so often. Once the page runs it returns a value. If I know there is more work to be done, I run the page again, right away, otherwise I...
what is the basic difference between stack and queue?
...al Model
Pancake Stack (LIFO)
The only way to add one and/or remove one is from the top.
Line Queue (FIFO)
When one arrives they arrive at the end of the queue and when one leaves they leave from the front of the queue.
Fun fact: the British refer to lines of people as a Queue
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