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In MySQL queries, why use join instead of where?
...s joins because the join conditions are not right next to the table names. If you have 6 tables being joined together, it is easy to miss one in the where clause. You will see this fixed all too often by using the distinct keyword. This is ahuge performance hit for the database. You can't get an acc...
How to do SELECT COUNT(*) GROUP BY and ORDER BY in Django?
...('actor').annotate(total=Count('actor')).order_by('total')
values() : specifies which columns are going to be used to "group by"
Django docs:
"When a values() clause is used to constrain the columns that are
returned in the result set, the method for evaluating annotations is
slightly different. I...
PHP - Merging two arrays into one array (also Remove Duplicates)
... tries to use the array values as strings. Hence the error @Ravi ran into. If your array is only strings then you don't need the third argument. If it is not a string, or the contents cannot be implicitly cast to a string, you will need the SORT_REGULAR argument.
– David Baucum...
What do REFRESH and MERGE mean in terms of databases?
...
What is the default (if we didnt set any CascadeType), and what is the most sensible/common to set?
– Rosdi Kasim
Jul 30 '10 at 4:56
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What is the difference between NULL, '\0' and 0?
In C, there appear to be differences between various values of zero -- NULL , NUL and 0 .
11 Answers
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How can you check which options vim was compiled with?
...ction with the feature you are looking for. The code below will return a 1 if it has the feature or 0 if it does not.
:echo has('python')
For a list of features see :h +feature-list
For more information see:
:h :version
:h has(
:h feature-list
...
How to commit no change and new message?
How can I make a new commit and create a new message if no changes are made to files?
5 Answers
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What does ~~ (“double tilde”) do in Javascript?
..., and the result is a number.
In other words, it yields:
function(x) {
if(x < 0) return Math.ceil(x);
else return Math.floor(x);
}
only if x is between -(231) and 231 - 1. Otherwise, overflow will occur and the number will "wrap around".
This may be considered useful to convert a functio...
multiple definition of template specialization when using different objects
When I use a specialized template in different object files, I get a "multiple definition" error when linking. The only solution I found involves using the "inline" function, but it just seems like some workaround. How do I solve that without using the "inline" keyword? If that's not possible, why?
...
Is there an easy way to add a border to the top and bottom of an Android View?
...m>
</layer-list>
The down side to this is that you have to specify an opaque background colour, as transparencies won't work. (At least i thought they did but i was mistaken). In the above example you can see that the solid colour of the first shape #FFdddddd is copied in the 2nd shapes ...