大约有 5,680 项符合查询结果（耗时：0.0134秒） [XML]
ActiveRecord.find(array_of_ids), preserving order
...ql called FIELD()
Here is how you could use it in .find():
>> ids = [100, 1, 6]
=> [100, 1, 6]
>> WordDocument.find(ids).collect(&:id)
=> [1, 6, 100]
>> WordDocument.find(ids, :order => "field(id, #{ids.join(',')})")
=> [100, 1, 6]
For new Version
>> WordDo...
What are the use cases for selecting CHAR over VARCHAR in SQL?
...er set) storing the word "FooBar"
CHAR(6) = 6 bytes (no overhead)
VARCHAR(100) = 8 bytes (2 bytes of overhead)
CHAR(10) = 10 bytes (4 bytes of waste)
The bottom line is CHAR can be faster and more space-efficient for data of relatively the same length (within two characters length difference).
Not...
How Scalable is SQLite? [closed]
... others that have lots of traffic. They suggest that if you have less than 100k hits per day, SQLite should work fine. And that was written before they delivered the "Writeahead Logging" feature.
If you want to speed things up with SQLite, do the following:
upgrade to SQLite 3.7.x
Enable write-...
How to draw a line in android
...(Canvas canvas) {
super.onDraw(canvas);
startX = 20;
startY = 100;
stopX = 140;
stopY = 30;
canvas.drawLine(startX, startY, stopX, stopY, paint);
}
Drawing a Line with View
If you only need a straight horizontal or vertical line, then the easiest way may be to just use a...
How to detect the physical connected state of a network cable/connector?
...ported link modes: 10baseT/Half 10baseT/Full
100baseT/Half 100baseT/Full
1000baseT/Full
Supports auto-negotiation: Yes
Advertised link modes: 10baseT/Half 10baseT/Full
100baseT/Half 100baseT/Full
...
onMeasure custom view explanation
...ure(int widthMeasureSpec, int heightMeasureSpec) {
int desiredWidth = 100;
int desiredHeight = 100;
int widthMode = MeasureSpec.getMode(widthMeasureSpec);
int widthSize = MeasureSpec.getSize(widthMeasureSpec);
int heightMode = MeasureSpec.getMode(heightMeasureSpec);
int hei...
How to center a button within a div?
I have a div that's width is 100%.
14 Answers
14
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Plot two histograms on single chart with matplotlib
... = [random.gauss(4,2) for _ in range(400)]
bins = numpy.linspace(-10, 10, 100)
pyplot.hist(x, bins, alpha=0.5, label='x')
pyplot.hist(y, bins, alpha=0.5, label='y')
pyplot.legend(loc='upper right')
pyplot.show()
share
...
Twitter Bootstrap: div in container with 100% height
...e page with a nav bar, and inside the container I want to add a div with 100% height (to the bottom of the screen). My css-fu is rusty, and I can't work this out.
...
Oracle 11.2.0.4 RAC FOR redhat 6.4 - 数据库(内核) - 清泛网 - 专注C/C++及内核技术
...st localhost.localdomain localhost6 localhost6.localdomain6
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172.16.110.101 dmjyrac1-vip
172.16.110.110 dmjyrac2
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172.16.110.102 dmjyrac-cluster dmjyrac-cluster-scan
10.10.120.100 dmjyrac1-priv
10.10.120.110 dmjyr...