大约有 43,000 项符合查询结果（耗时：0.0871秒） [XML]
How do I check if a list is empty?
For example, if passed the following:
27 Answers
27
...
SQL WHERE ID IN (id1, id2, …, idn)
I need to write a query to retrieve a big list of ids.
9 Answers
9
...
What's the best strategy for unit-testing database-driven applications?
I work with a lot of web applications that are driven by databases of varying complexity on the backend. Typically, there's an ORM layer separate from the business and presentation logic. This makes unit-testing the business logic fairly straightforward; things can be implemented in discrete modul...
Is there a good reason I see VARCHAR(255) used so often (as opposed to another length)?
In multiple courses, books, and jobs, I have seen text fields defined as VARCHAR(255) as kind of the default for "shortish" text. Is there any good reason that a length of 255 is chosen so often, other than being a nice round number ? Is it a holdout from some time in the past when there was a go...
How exactly does a generator comprehension work?
What does generator comprehension do? How does it work? I couldn't find a tutorial about it.
6 Answers
...
Is there a way to cache GitHub credentials for pushing commits?
...itched to synchronizing my repositories to https:// on GitHub (due to firewall issues), and it asks for a password every time.
...
Share cookie between subdomain and domain
I have two questions. I understand that if I specify the domain as .mydomain.com (with the leading dot) in the cookie that all subdomains can share a cookie.
...
Alternatives to JavaScript
At the moment, the only fully supported language, and the de-facto standard for DOM tree manipulation in the browser is JavaScript. It looks like it has deep design issues that make it a minefield of bugs and security holes for the novice.
...
In Python how should I test if a variable is None, True or False
I have a function that can return one of three things:
6 Answers
6
...
Python pandas: fill a dataframe row by row
The simple task of adding a row to a pandas.DataFrame object seems to be hard to accomplish. There are 3 stackoverflow questions relating to this, none of which give a working answer.
...