大约有 47,000 项符合查询结果（耗时：0.0613秒） [XML]
Android custom dropdown/popup menu
... android:paddingEnd="10dip">
<ImageView
android:id="@+id/shoe_select_icon"
android:layout_width="30dp"
android:layout_height="30dp"
android:layout_gravity="center_vertical"
android:scaleType="fitXY" />
<TextView
android:id="@+id/shoe_select_text"
android:l...
Compare two data.frames to find the rows in data.frame 1 that are not present in data.frame 2
...ata.frame(a = 1:3, b=letters[1:3])
require(sqldf)
a1NotIna2 <- sqldf('SELECT * FROM a1 EXCEPT SELECT * FROM a2')
And the rows which are in both data frames:
a1Ina2 <- sqldf('SELECT * FROM a1 INTERSECT SELECT * FROM a2')
The new version of dplyr has a function, anti_join, for exactly the...
data.table vs dplyr: can one do something well the other can't or does poorly?
... ## data.table syntax
left_join(DT2, DT1) ## dplyr syntax
# 2. select columns while join
DT1[DT2, .(z, i.mul)]
left_join(select(DT2, x, y, mul), select(DT1, x, y, z))
# 3. aggregate while join
DT1[DT2, .(sum(z) * i.mul), by = .EACHI]
DF1 %>% group_by(x, y) %>% summarise(z = su...
Hidden Features of MySQL
...that has an integer type,
you can also refer to the column as "_rowid" in SELECT statements.
In MySQL, the name of a PRIMARY KEY is PRIMARY
Currently, only InnoDB (v5.1?) tables support foreign keys.
Usually, you create all the indexes you need when you are creating tables.
Any column declared...
How to reformat JSON in Notepad++?
...,
"onclick" : "CloseDoc()"
}
]
}
}
}
Tip: Select the code you want to reformat, then Plugins | JSTool | JSFormat.
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How do I specify different layouts for portrait and landscape orientations?
...mes depending on orientation and resolution, the device will automatically select the right one for its screen settings
More info here:
http://developer.android.com/guide/practices/screens_support.html
under "Resource directory qualifiers for screen size and density"
...
Increment value in mysql update query
...ion to numbers.
To demonstrate, the following will produce the result 6:
SELECT ' 05.05 '+'.95';
String concatenation in MySQL requires the CONCAT() function so there is no ambiguity here and MySQL converts the strings to floats and adds them together.
I actually think the reason the initial q...
How to show SQL queries run in the Rails console?
...ecord::Relation’s to_sql method:
User.where(:id => 3).to_sql
#=> "SELECT \"users\".* FROM \"users\" WHERE \"users\".\"id\" = 3"
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Comparison of full text search engine - Lucene, Sphinx, Postgresql, MySQL?
... up the firstname field as shown.
http://localhost:8983/solr/collection1/select?q=firstname:john^2&lastname:john
As you can see, firstname field is boosted up with a score of 2.
More on SolrRelevancy
searching and indexing speed
The speed is unbelievably fast and no compromise o...
unsigned APK can not be installed
...ps.)
Install your app onto the emulator.
Once it is installed goto DDMS, select the current running app under the devices window. This will then show all the files related to it under the file explorer.
Under file explorer go to data->app and select your APK (which is the package name of the ap...