大约有 42,000 项符合查询结果（耗时：0.0325秒） [XML]
MySQL select one column DISTINCT, with corresponding other columns
...STINCT results from the FirstName column, but I need the corresponding ID and LastName .
12 Answers
...
How do I perform the SQL Join equivalent in MongoDB?
... The new $lookup operator added to the aggregation pipeline is essentially identical to a left outer join:
https://docs.mongodb.org/master/reference/operator/aggregation/lookup/#pipe._S_lookup
From the docs:
{
$lookup:
{
from: <collection to join>,
localField: <fiel...
List of lists changes reflected across sublists unexpectedly
...s visible via all three references to it:
x = [1] * 4
l = [x] * 3
print(f"id(x): {id(x)}")
# id(x): 140560897920048
print(
f"id(l[0]): {id(l[0])}\n"
f"id(l[1]): {id(l[1])}\n"
f"id(l[2]): {id(l[2])}"
)
# id(l[0]): 140560897920048
# id(l[1]): 140560897920048
# id(l[2]): 140560897920048
x...
MySQL Insert into multiple tables? (Database normalization?)
...s (username, password)
VALUES('test', 'test');
INSERT INTO profiles (userid, bio, homepage)
VALUES(LAST_INSERT_ID(),'Hello world!', 'http://www.stackoverflow.com');
COMMIT;
Have a look at LAST_INSERT_ID() to reuse autoincrement values.
Edit: you said "After all this time trying to figure it ...
Random record in ActiveRecord
...
I haven't found an ideal way to do this without at least two queries.
The following uses a randomly generated number (up to the current record count) as an offset.
offset = rand(Model.count)
# Rails 4
rand_record = Model.offset(offset).first...
Select last row in MySQL
...last of all the rows in the table, then this is finally the time where MAX(id) is the right answer! Kind of:
SELECT fields FROM table ORDER BY id DESC LIMIT 1;
share
|
improve this answer
...
Do DOM tree elements with ids become global variables?
Working on an idea for a simple HTMLElement wrapper I stumbled upon the following for Internet Explorer and Chrome :
5 An...
Typing Enter/Return key using Python and Selenium?
...
JAVA
driver.findElement(By.id("Value")).sendKeys(Keys.RETURN);
OR,
driver.findElement(By.id("Value")).sendKeys(Keys.ENTER);
PYTHON
from selenium.webdriver.common.keys import Keys
driver.find_element_by_name("Value").send_keys(Keys.RETURN)
OR,
drive...
get an element's id
Is there another way to get an DOM element's ID?
8 Answers
8
...
How to implement Android Pull-to-Refresh
In Android applications such as Twitter (official app), when you encounter a ListView, you can pull it down (and it will bounce back when released) to refresh the content.
...