大约有 43,000 项符合查询结果（耗时：0.0598秒） [XML]
Is it ever advantageous to use 'goto' in a language that supports loops and functions? If so, why?
...about this one:
a[900]; b;c;d=1 ;e=1;f; g;h;O; main(k,
l)char* *l;{g= atoi(* ++l); for(k=
0;k*k< g;b=k ++>>1) ;for(h= 0;h*h<=
g;++h); --h;c=( (h+=g>h *(h+1)) -1)>>1;
while(d <=g){ ++O;for ...
HTTP Error 403.14 - Forbidden - The Web server is configured to not list the contents of this direct
...d features" in Server Manager.
In Wizard scroll down to the Web server and select : Web Server -> Application Development. Select all except CGI from the list as shown in the screen shot
Finally hit next and Install.
Restart IIS
Your website may start working.
...
Why and not taking font-family and font-size from body?
...es if you want to change their font/text styles - should be easy enough by selecting them though, as you've just done.
As far as I know, only form elements are affected. Off the top of my head: input, button, textarea, select.
...
What are the main purposes of using std::forward and which problems it solves?
...f we leave t1 & t2 as lvalue?
If, after instantiating, T1 is of type char, and T2 is of a class, you want to pass t1 per copy and t2 per const reference. Well, unless inner() takes them per non-const reference, that is, in which case you want to do so, too.
Try to write a set of outer() func...
How do you detect Credit card type based on number?
...: before processing a cardholder PAN, strip any whitespace and punctuation characters from the input. Why? Because it’s typically much easier to enter the digits in groups, similar to how they’re displayed on the front of an actual credit card, i.e.
4444 4444 4444 4444
is much easier to ent...
Difference between CTE and SubQuery?
...
CTE's are most useful for recursion:
WITH hier(cnt) AS (
SELECT 1
UNION ALL
SELECT cnt + 1
FROM hier
WHERE cnt < @n
)
SELECT cnt
FROM hier
will return @n rows (up to 101). Useful for calendars, dummy rowsets etc.
They are als...
Remove columns from dataframe where ALL values are NA
...
dplyr now has a select_if verb that may be helpful here:
library(dplyr)
temp <- data.frame(x = 1:5, y = c(1,2,NA,4, 5), z = rep(NA, 5))
not_all_na <- function(x) any(!is.na(x))
not_any_na <- function(x) all(!is.na(x))
> temp
...
If table exists drop table then create it, if it does not exist just create it
...up the old table,
obviously.
Wrapping all statements with something like SELECT GET_LOCK('__upgrade', -1); ... DO RELEASE_LOCK('__upgrade'); allows to just invoke all statements sequentially without error checking, but I don't think it's a good idea: complexity increases and locking functions in M...
How to log PostgreSQL queries?
...ement = 'all'
#logging_collector = off to logging_collector = on
Optional: SELECT set_config('log_statement', 'all', true);
sudo /etc/init.d/postgresql restart or sudo service postgresql restart
Fire query in postgresql select 2+2
Find current log in /var/lib/pgsql/9.2/data/pg_log/
The log files t...
内存优化总结:ptmalloc、tcmalloc和jemalloc - 操作系统(内核) - 清泛网 - ...
... 总共32个vcpu。 16个table，每个5M row。
OLTP_RO测试包含5个select查询：select_ranges, select_order_ranges, select_distinct_ranges, select_sum_ranges,
可以看到在多核心或者多线程的场景下， jemalloc和tcmalloc带来的tps增加非常明显。
参考资料
glibc...