大约有 12,000 项符合查询结果（耗时：0.0320秒） [XML]
datetime.parse and making it work with a specific format
... By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy
...
sql primary key and index
...ed in PRIMARY KEY, but allowed in UNIQUE index; and like in set operators (UNION, EXCEPT, INTERSECT), here NULL = NULL which means that you can have only one value as two NULLs are find as duplicates of each other;
only one PRIMARY KEY may exists per table while 999 unique indexes can be created
whe...
What is the most effective way for float and double comparison?
...AGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY ...
How do you find the disk size of a Postgres / PostgreSQL table and its indexes
... where table_schema = 'public' and table_type = 'BASE TABLE'
union
-- materialized views
SELECT oid::regclass::text as table_name
FROM pg_class
WHERE relkind = 'm'
order by table_name
) AS all_tables
-- ORDER BY total_size DESC
order ...
How to read a local text file?
...nsistent handling of: URL schemes, Redirects, Cross-origin semantics, CSP, Service workers, Mixed Content, Referer". I guess this means goodbye to good ol'FileReaders and HttpRequests (and I won't miss them a bit ;)
– Armfoot
Oct 25 '17 at 17:17
...
How can I set the aspect ratio in matplotlib?
I'm trying to make a square plot (using imshow), i.e. aspect ratio of 1:1, but I can't. None of these work:
5 Answers
...
Is there any pythonic way to combine two dicts (adding values for keys that appear in both)?
...':4, 'd':5}
>>> c = {x: A.get(x, 0) + B.get(x, 0) for x in set(A).union(B)}
>>> print(c)
{'a': 1, 'c': 7, 'b': 5, 'd': 5}
share
|
improve this answer
|
fo...
How to create enum like type in TypeScript?
...llo"
They are not very useful on their own but can be combined in a type union to create a powerful (and useful) abstraction e.g.:
type CardinalDirection =
"North"
| "East"
| "South"
| "West";
function move(distance: number, direction: CardinalDirection) {
// ...
}
move(1,"N...
Descending order by date filter in AngularJs
...
see w3schools samples:
https://www.w3schools.com/angular/angular_filters.asp
https://www.w3schools.com/angular/tryit.asp?filename=try_ng_filters_orderby_click
then add the "reverse" flag:
<!DOCTYPE html>
<html>
<script src="https://ajax.googleapis.com/ajax/libs/angularjs/1.6.4/ang...
When should you NOT use a Rules Engine? [closed]
... during implementation / on-boarding process, and then any major change on service request basis.
– Eric Xin Zhang
Aug 23 '18 at 5:27
...