大约有 45,000 项符合查询结果（耗时：0.0412秒） [XML]
Simulate CREATE DATABASE IF NOT EXISTS for PostgreSQL?
...
Restrictions
You can ask the system catalog pg_database - accessible from any database in the same database cluster. The tricky part is that CREATE DATABASE can only be executed as a single statement. The manual:
CREATE DATABASE cannot be executed inside a transaction b...
How do I format a date in Jinja2?
...and print) the strftime() method in your template, for example
{{ car.date_of_manufacture.strftime('%Y-%m-%d') }}
Another, sightly better approach would be to define your own filter, e.g.:
from flask import Flask
import babel
app = Flask(__name__)
@app.template_filter()
def format_datetime(val...
How do you trigger a block after a delay, like -performSelector:withObject:afterDelay:?
...
I think you're looking for dispatch_after(). It requires your block to accept no parameters, but you can just let the block capture those variables from your local scope instead.
int parameter1 = 12;
float parameter2 = 144.1;
// Delay execution of my block ...
Passing Data between View Controllers
...A)
// in ContollerA.m
- (void)viewDidLoad {
[super viewDidLoad];
__unsafe_unretained typeof(self) weakSelf = self;
self.selectedVoucherBlock = ^(NSString *voucher) {
weakSelf->someLabel.text = voucher;
};
}
Go to Controller B
UIStoryboard *storyboard = [UIStoryboard s...
Get img thumbnails from Vimeo?
...ic video,
use the following url:
http://vimeo.com/api/v2/video/video_id.output
video_id The ID of the video you want information for.
output Specify the
output type. We currently offer JSON,
PHP, and XML formats.
So getting this URL http://vimeo.com/api/v2/video/6271487.xml
...
Circular gradient in android
...ource with a px or dp value, like: android:gradientRadius="@dimen/gradient_radius"
– Bolling
Mar 3 '15 at 21:20
2
...
How to allocate aligned memory only using the standard library?
... malloc(1024+16);
void *ptr = ((char *)mem+16) & ~ 0x0F;
memset_16aligned(ptr, 0, 1024);
free(mem);
}
Fixed answer
{
void *mem = malloc(1024+15);
void *ptr = ((uintptr_t)mem+15) & ~ (uintptr_t)0x0F;
memset_16aligned(ptr, 0, 1024);
free(mem);
}
Explanation as ...
How do I design a class in Python?
...function so that it only happens once. Something like:
class Dog:
def __init__(self):
self._footsteps=None
def footstep(self,n):
if not self._footsteps:
self.readInFootsteps(...)
return self._footsteps[n]
[This is now a sort of caching pattern. The first time it goe...
How to serialize a TimeSpan to XML
... this:
[XmlIgnore]
public TimeSpan TimeSinceLastEvent
{
get { return m_TimeSinceLastEvent; }
set { m_TimeSinceLastEvent = value; }
}
// XmlSerializer does not support TimeSpan, so use this property for
// serialization instead.
[Browsable(false)]
[XmlElement(DataType="duration", ElementNa...
How do I list all tables in a schema in Oracle SQL?
...BA role.
With any of those, you can select:
SELECT DISTINCT OWNER, OBJECT_NAME
FROM DBA_OBJECTS
WHERE OBJECT_TYPE = 'TABLE'
AND OWNER = '[some other schema]'
Without those system privileges, you can only see tables you have been granted some level of access to, whether directly or through...