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How to convert a string to an integer in JavaScript?
...dgetsSold is now 97
It's good practice to always specify the radix as the second argument. In older browsers, if the string started with a 0, it would be interpreted as octal if the radix wasn't specified which took a lot of people by surprise. The behaviour for hexadecimal is triggered by having...
DateTime2 vs DateTime in SQL Server
...hey are more portable.
time, datetime2 and datetimeoffset
provide more seconds precision.
datetimeoffset provides time zone
support for globally deployed
applications.
datetime2 has larger date range, a larger default fractional precision, and optional user-specified precision. Also depe...
Converting datetime.date to UTC timestamp in Python
...ents date in UTC without calendar.timegm():
DAY = 24*60*60 # POSIX day in seconds (exact value)
timestamp = (utc_date.toordinal() - date(1970, 1, 1).toordinal()) * DAY
timestamp = (utc_date - date(1970, 1, 1)).days * DAY
How can I get a date converted to seconds since epoch according to UTC?
To ...
How to change the foreign key referential action? (behavior)
... KEY `fk_name`;
notice constraint is deleted, column is not deleted
Second step, ADD new CONSTRAINT:
ALTER TABLE `table1`
ADD CONSTRAINT `fk_name`
FOREIGN KEY (`fk_table2_id`) REFERENCES `table2` (`t2`) ON DELETE CASCADE;
adding constraint, column is already there
Example:...
How to extract epoch from LocalDate and LocalDateTime?
...DateTime do not contain information about the timezone or time offset, and seconds since epoch would be ambigious without this information. However, the objects have several methods to convert them into date/time objects with timezones by passing a ZoneId instance.
LocalDate
LocalDate date = ...;
...
Summarizing multiple columns with dplyr? [duplicate]
... FALSE
)
#> # A tibble: 3 x 6
#> expression min median `itr/sec` mem_alloc `gc/sec`
#> <bch:expr> <bch:tm> <bch:tm> <dbl> <bch:byt> <dbl>
#> 1 dplyr 2.81ms 2.85ms 328. NA 17.3
#> 2 purrrlyr 7.96ms 8.0...
How to speed up insertion performance in PostgreSQL
...hours on the same issue today. Inserts go at a 'regular' speed (less than 3sec per 100K) up until to 5MI (out of total 30MI) rows and then the performance sinks drastically (all the way down to 1min per 100K).
I will not list all of the things that did not work and cut straight to the meat.
I dr...
Getting key with maximum value in dictionary?
...
976: 24, 166: 112}
And the test results under Python 3.2:
rate/sec f4 f3 f3b f8 f5 f2 f4b f6 f7 f1
f4 454 -- -2.5% -96.9% -97.5% -98.6% -98.6% -98.7% -98.7% -98.9% -99.0%
f3 466 2.6% -- -96.8% -97.4% -98.6% -98.6% -98....
Spring Test & Security: How to mock authentication?
... figure out how to unit test if my the URLs of my controllers are properly secured. Just in case someone changes things around and accidentally removes security settings.
...
Generating random integer from a range
...gh_resolution_clock Clock;
typedef std::chrono::duration<double> sec;
Clock::time_point t0 = Clock::now();
const int N = 10000000;
typedef std::minstd_rand G;
G g;
typedef std::uniform_int_distribution<> D;
D d(-57, 365);
int c = 0;
for (int i = 0; i &...