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MySQL: selecting rows where a column is null
I'm having a problem where when I try to select the rows that have a NULL for a certain column, it returns an empty set. However, when I look at the table in phpMyAdmin, it says null for most of the rows.
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minimum double value in C/C++
...tion just has to work around it. See the floating-point model in 5.2.4.2.2 Characteristics of floating types <float.h> p2 of C99 (may have been moved elsewhere since then).
– user743382
Nov 10 '14 at 22:23
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MySQL “NOT IN” query
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To use IN, you must have a set, use this syntax instead:
SELECT * FROM Table1 WHERE Table1.principal NOT IN (SELECT principal FROM table2)
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Pipe to/from the clipboard in Bash script
...lets you talk to it.
In the case of X, there's xclip (and others). xclip -selection c will send data to the clipboard that works with Ctrl + C, Ctrl + V in most applications.
If you're on Mac OS X, there's pbcopy. e.g cat example.txt | pbcopy
If you're in Linux terminal mode (no X) then look into...
How to use conditional breakpoint in Eclipse?
...t editor margin or in the Breakpoints
view in the Debug perspective, and select the breakpoint’s properties.
In the dialog box, check Enable Condition, and enter an arbitrary Java
condition, such as list.size()==0. Now, each time the breakpoint is
reached, the expression is evaluated in th...
Removing duplicate rows from table in Oracle
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Use the rowid pseudocolumn.
DELETE FROM your_table
WHERE rowid not in
(SELECT MIN(rowid)
FROM your_table
GROUP BY column1, column2, column3);
Where column1, column2, and column3 make up the identifying key for each record. You might list all your columns.
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What does immutable mean?
...ng the same data.
Of course, since the three strings all contain the same character data, using the equals method will return true.
(Both types of string construction are immutable, of course)
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How to trick an application into thinking its stdout is a terminal, not a pipe
...lt;&- script -qfc "git status" /dev/null | less -R . Those first few characters close stdin for this one commmand.
– Aaron McDaid
Nov 26 '14 at 13:54
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How do I find the location of the executable in C? [duplicate]
...eir tracks, then execl("/home/hacker/.hidden/malicious", "/bin/ls", "-s", (char *)0); leaves argv[0] with an absolute pathname that has nothing whatsoever to do with the name of the file executed. The other information is useful, though; thanks.
– Jonathan Leffler
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How to call a PHP function on the click of a button
..."insert" value="insert" />
<input type="submit" class="button" name="select" value="select" />
jQuery:
$(document).ready(function(){
$('.button').click(function(){
var clickBtnValue = $(this).val();
var ajaxurl = 'ajax.php',
data = {'action': clickBtnValu...