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What is the lifetime of a static variable in a C++ function?
... emitter a("in if");
static emitter b("in foo");
}
int main(int argc, char*[])
{
foo(argc != 2);
if (argc == 3)
foo(false);
}
Output:
C:>sample.exe
Created in foo
Destroyed in foo
C:>sample.exe 1
Created in if
Created in foo
Destroyed in foo
Destroyed in if
C:>sample...
MIN/MAX vs ORDER BY and LIMIT
...oks like MIN() is able to simply pluck the smallest value from the index ('Select tables optimized away' and 'NULL' rows) whereas the SORT and LIMIT still needs needs to do an ordered traversal of the index (106,000 rows). The actual performance impact is probably negligible.
It looks like MIN() i...
Repeat string to certain length
... to compute the number of full repetitions needed, and the number of extra characters, all at once:
def pillmod_repeat_to_length(s, wanted):
a, b = divmod(wanted, len(s))
return s * a + s[:b]
Which is better? Let's benchmark it:
>>> import timeit
>>> timeit.repeat('sche...
Select text on input focus
I have a text input. When the input receives focus I want to select the text inside of the input.
10 Answers
...
MySQL selecting yesterday's date
...get yesterday's date is:
subdate(current_date, 1)
Your query would be:
SELECT
url as LINK,
count(*) as timesExisted,
sum(DateVisited between UNIX_TIMESTAMP(subdate(current_date, 1)) and
UNIX_TIMESTAMP(current_date)) as timesVisitedYesterday
FROM mytable
GROUP BY 1
For the ...
SQL Server dynamic PIVOT query?
... @cols AS NVARCHAR(MAX),
@query AS NVARCHAR(MAX);
SET @cols = STUFF((SELECT distinct ',' + QUOTENAME(c.category)
FROM temp c
FOR XML PATH(''), TYPE
).value('.', 'NVARCHAR(MAX)')
,1,1,'')
set @query = 'SELECT date, ' + @cols + ' from
(...
sed or awk: delete n lines following a pattern
...;/div>/,$d' out.txt but it gives error saying : sed: -e expression #1, char 24: extra characters after command Thanks in advance.
– N mol
Aug 24 '13 at 2:37
8
...
android studio 0.4.2: Gradle project sync failed error
...butions/gradle-1.9-all.zip
After open your project in Android Studio and select the build.gradle file in the /src directory and edit it to this :
dependencies {
classpath 'com.android.tools.build:gradle:0.7.+'
}
After fixing it like this I discovered this article :
http://tools.andr...
How do you find the row count for all your tables in Postgres
...th their own tradeoffs.
If you want a true count, you have to execute the SELECT statement like the one you used against each table. This is because PostgreSQL keeps row visibility information in the row itself, not anywhere else, so any accurate count can only be relative to some transaction. Yo...
href=“tel:” and mobile numbers
...
Maybe the solution involves escape characters of some sort? or unicode chars to express individual characters?
– Tropicalrambler
Jul 8 at 23:04
...