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How do I check if a column is empty or null in MySQL?
... '' = ' ' works in SQLServer but not in SQLite, as far as I can tell, from testing it now.
– Magne
Oct 3 '17 at 9:59
add a comment
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How do I prevent the modification of a private field in a class?
...ll never change
Here is a simple example of how to use it:
public class Test
{
private String[] arr = new String[]{"1","2"};
public ImmutableList<String> getArr()
{
return ImmutableList.copyOf(arr);
}
}
...
jQuery Determine if a matched class has a given id
...that lets your determine whether an element has certain qualities. You can test a jQuery collection against a string selector, an HTML Element, or another jQuery object. In this case, we'll just check it against a string selector:
$(".bar:first").is("#foo"); // TRUE if first '.bar' in document is a...
How do I replace NA values with zeros in an R dataframe?
...ults.
If you are struggling with massive dataframes, data.table is the fastest option of all: 40% faster than the standard Base R approach. It also modifies the data in place, effectively allowing you to work with nearly twice as much of the data at once.
A clustering of other helpful tidyverse ...
Iterate over each line in a string in PHP
...lse) {
# do something with $line
$line = strtok( $separator );
}
Testing the performance, I iterated 100 times over a test file with 17 thousand lines: preg_split took 27.7 seconds, whereas strtok took 1.4 seconds.
Note that though the $separator is defined as "\r\n", strtok will separate...
Display numbers with ordinal suffix in PHP
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@HafezDivandari - are you sure? Just tested with 7.1.19 and seems to work fine
– Iacopo
Dec 5 '18 at 9:35
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Stack Memory vs Heap Memory [duplicate]
... case of C++, the code is not run in either the stack or the heap. You can test what happens if you run out of heap memory by repeatingly calling new to allocate memory in a loop without calling delete to free it it. But make a system backup before doing this.
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How to make an anchor tag refer to nothing?
... It seems that href="javascript:" is also enough and works in the latest major browsers. No need for the semicolon, in fact PhpStorm even suggests to remove it.
– jlh
Jul 24 '17 at 13:37
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Pretty graphs and charts in Python [closed]
...'s comment, its very easy to label axis and define the colors used...Check tests.py for examples. Anyways, Thanks for a nice lib.
– Daniel Magnusson
Nov 13 '09 at 8:05
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How can I apply a border only inside a table?
...}
table td, table th {
border: 1px solid black;
}
view example ...
tested in FF 3.6 and Chromium 5.0, IE lacks support; from W3C:
Borders with the 'border-style' of 'hidden' take precedence over all other conflicting borders. Any border with this value suppresses all borders at this loca...