大约有 44,000 项符合查询结果（耗时：0.0559秒） [XML]
TransactionManagementError “You can't execute queries until the end of the 'atomic' block” while usi
...or database interaction, unittest.TestCase for other simple test, it works now!
share
|
improve this answer
|
follow
|
...
Is it secure to store passwords as environment variables (rather than as plain text) in config files
... order of increasing strength) :
No security. Plain text. Anyone that knows where to look, can access the data.
Security by Obfuscation. You store the data (plaintext) someplace tricky, like an environment variable, or in a file that is meant to look like a configuration file. An attacker will...
The difference between the Runnable and Callable interfaces in Java
...le : If you are trying to retrieve a value from a task, then use Callable. Now callable on its own will not do the job. You will need a Future that you wrap around your Callable and get your values on future.get (). Here the calling thread will be blocked till the Future comes back with results whic...
Generate a UUID on iOS from Swift
...
Graveyard nitpick here but I don't know why lowercase UUID is preferable to a regular UUID.
– Alex Kornhauser
Nov 1 '18 at 2:35
add a co...
Explicit vs implicit SQL joins
...
The first answer you gave uses what is known as ANSI join syntax, the other is valid and will work in any relational database.
I agree with grom that you should use ANSI join syntax. As they said, the main reason is for clarity. Rather than having a where clause w...
Get attribute name value of
...lve the problem. OP wants to get the name value; this assumes you already know it.
– felwithe
May 1 '15 at 22:06
add a comment
|
...
How to select all records from one table that do not exist in another table?
...n are just null. Then you tell, ok i only want that are null. This way you now have all rows in A that didn't have a match In B
– Muhammad Umer
Mar 6 '18 at 18:02
7
...
What is the difference between the bridge pattern and the strategy pattern?
...apsulate out a specific behavior and not the entire implementation) would know/contain the strategy interface reference and the implementation to invoke the strategy behavior on it.
Intent is ability to swap behavior at runtime
class Context {
IStrategy strategyReference;
void strategic...
How to use Bash to create a folder if it doesn't already exist?
...
Wow! Knowing that "[" is a command in bash is such an eye-opener. I feel like a lot of issues with my bash scripts are now resolved!
– raluru
Nov 5 '19 at 11:13
...
Is it bad practice to make a setter return “this”?
...en:
You need to set many fields at once (including at construction)
you know which fields you need to set at the time you're writing the code, and
there are many different combinations for which fields you want to set.
Alternatives to this method might be:
One mega constructor (downside: you ...