大约有 2,700 项符合查询结果（耗时：0.0290秒） [XML]
Adding :default => true to boolean in existing Rails column
...
change_column :things, :price_1, :integer, default: 123, null: false
Seems to be best way to add a default to an existing column that doesn't have null: false already.
Otherwise:
change_column :things, :price_1, :integer, default: 123
Some research I did on this:
https:...
MySQL Query GROUP BY day / month / year
...swered Jun 9 '13 at 9:17
mr.baby123mr.baby123
1,7841919 silver badges1212 bronze badges
...
How to resolve “must be an instance of string, string given” prior to PHP 7?
...on __toString()
{
return $this->Text;
}
}
function Test123(string $s)
{
echo $s;
}
Test123(new string("Testing"));
share
|
improve this answer
|
fol...
What is the behavior difference between return-path, reply-to and from?
...mpany.com>
Subject: Super simple email
Reply-To: <coolstuff-threadId=123@mymailinglist.com>
This is a very simple body.
Now, let's say you are going to send it from a mailing list, that implements VERP (or some other bounce tracking mechanism that uses a different return-path). Lets sa...
REST authentication and exposing the API key
...eed REFERER. Still, it is secure:
When our get-csrf-token.js?apiKey=abc123 is requested:
Look up the key abc123 in the database and get a list of valid domains for that key.
Look for the CSRF validation cookie. If it does not exist, generate a secure random value and put it in a HTTP-only sess...
Formatting Phone Numbers in PHP
... SMS app and need to be able to convert the sender's phone number from +11234567890 to 123-456-7890 so it can be compared to records in a MySQL database .
...
Why is a combiner needed for reduce method that converts type in java 8
... answered Sep 4 '15 at 7:39
quiz123quiz123
3655 bronze badges
...
The difference between sys.stdout.write and print?
... open('log.txt', 'w') # redirect all prints to this log file
print("testing123") # nothing appears at interactive prompt
print("another line") # again nothing appears. it's written to log file instead
sys.stdout.close() # ordinary file object
sys.stdout = tem...
Two-dimensional array in Swift
... = 18
OR
let myVar = 18
arr[0][1] = myVar
Change sub array
arr[1] = [123, 456, 789]
OR
arr[0] += 234
OR
arr[0] += [345, 678]
If you had 3x2 array of 0(zeros) before these changes, now you have:
[
[0, 0, 234, 345, 678], // 5 elements!
[123, 456, 789],
[0, 0]
]
So be aware tha...
How to generate all permutations of a list?
...
Combination (order does NOT matter):
print list(itertools.combinations('123', 2))
[('1', '2'), ('1', '3'), ('2', '3')]
Cartesian product (with several iterables):
print list(itertools.product([1,2,3], [4,5,6]))
[(1, 4), (1, 5), (1, 6),
(2, 4), (2, 5), (2, 6),
(3, 4), (3, 5), (3, 6)]
Cartesia...