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Initializing a member array in constructor initializer
...e about the following case, but some compilers do allow it.
struct A {
char foo[6];
A():foo("hello") { } /* valid? */
};
See this GCC PR for further details.
Do C++0x initializer lists solve the problem?
Yes, they do. However your syntax is invalid, I think. You have to use braces dir...
Generic TryParse
... answered Jul 1 '11 at 22:11
Charlie BrownCharlie Brown
79755 silver badges22 bronze badges
...
jQuery get selected option value (not the text, but the attribute 'value')
...
04/2020: Corrected old answer
Use :selected psuedo selector on the selected options and then use the .val function to get the value of the option.
$('select[name=selector] option').filter(':selected').val()
Side note: Using filter is better then using :sele...
Which is fastest? SELECT SQL_CALC_FOUND_ROWS FROM `table`, or SELECT COUNT(*)
...irm this - I just updated a query with 4 joins on a 168,000 row database. Selecting just the first 100 rows with a SQL_CALC_FOUND_ROWS took over 20 seconds; using a separate COUNT(*) query took under 5 seconds (for both count + results queries).
– Sam Dufel
Ju...
Capture characters from standard input without waiting for enter to be pressed
...up so infrequently for me. But in C or C++, what is the best way to read a character from standard input without waiting for a newline (press enter).
...
How do SQL EXISTS statements work?
... criteria -- this is why it can be faster than IN. Also be aware that the SELECT clause in an EXISTS is ignored - IE:
SELECT s.*
FROM SUPPLIERS s
WHERE EXISTS (SELECT 1/0
FROM ORDERS o
WHERE o.supplier_id = s.supplier_id)
...should hit a division by zero error...
What XML parser should I use in C++? [closed]
...what library you should use depends on your needs. Here's a convenient flowchart:
So the first question is this: What do you need?
I Need Full XML Compliance
OK, so you need to process XML. Not toy XML, real XML. You need to be able to read and write all of the XML specification, not just the low-l...
COUNT(*) vs. COUNT(1) vs. COUNT(pk): which is better? [duplicate]
...for all your queries that need to count everything, even for joins, use *
SELECT boss.boss_id, COUNT(subordinate.*)
FROM boss
LEFT JOIN subordinate on subordinate.boss_id = boss.boss_id
GROUP BY boss.id
But don't use COUNT(*) for LEFT joins, as that will return 1 even if the subordinate table doe...
Escape double quotes in parameter
...ve all the quotes here and place the parameter value in a string used in a select query filter? Can someone help?
– SFDC_Learner
Nov 24 '15 at 16:21
...
Javascript seconds to minutes and seconds
... ... modify (9<s?':':':0') to (10>s?':0':':') (adding 1 char but 'sacrificing' 5 out of 6 true-paths to false-paths) OR (10<=s?':':':0') (adding 2 chars but maintaining 5 out of 6 true paths). Then I advise to change that final trailing +s to +(s|0) instead of Math.floor(s), as...