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MySQL: Insert record if not exists in table
...tnames (name, address, tele)
SELECT * FROM (SELECT 'Rupert', 'Somewhere', '022') AS tmp
WHERE NOT EXISTS (
SELECT name FROM table_listnames WHERE name = 'Rupert'
) LIMIT 1;
Query OK, 1 row affected (0.00 sec)
Records: 1 Duplicates: 0 Warnings: 0
SELECT * FROM `table_listnames`;
+----+------...
How do you add an array to another array in Ruby and not end up with a multi-dimensional result?
...note the asterisk, and that a2 is the receiver
or splice:
a1[a1.length, 0] = a2
a1[a1.length..0] = a2
a1.insert(a1.length, *a2)
or append and flatten:
(a1 << a2).flatten! # a call to #flatten instead would return a new array
...
Add a number to each selection in Sublime Text 2, incremented once per selection
...which will be added to the index for
each selection.
P must be > 0 and will be used to pad the index with
leading zeroes.
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How can I create a Set of Sets in Python?
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answered May 9 '11 at 0:18
a3nma3nm
7,50155 gold badges2525 silver badges3737 bronze badges
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SQLite select where empty?
...ere coalesce(some_column, '') = ''
of
where ifnull(length(some_column), 0) = 0
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Do you use NULL or 0 (zero) for pointers in C++?
...as bolted on top of C, you could not use NULL as it was defined as (void*)0 . You could not assign NULL to any pointer other than void* , which made it kind of useless. Back in those days, it was accepted that you used 0 (zero) for null pointers.
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Best practices/guidance for maintaining assembly version numbers
...context we use TeamCity and Subversion/Git. TeamCity is free for a small (10) number of projects and is a very good build server but there are others, some of which are completely free.
What a version number means
What a version means to one person may mean something different to another, the gene...
How is “=default” different from “{}” for default constructor and destructor?
...
105
This is a completely different question when asking about constructors than destructors.
If yo...
How to combine multiple conditions to subset a data-frame using “OR”?
... it is to be handled as I intended, since ...
> NA & 1
[1] NA
> 0 & NA
[1] FALSE
Order of arguments may matter when using '&".
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Comparing two CGRects
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250
Use this:
if (CGRectEqualToRect(self.view.frame, rect)) {
// do some stuff
}
...
