大约有 40,000 项符合查询结果（耗时：0.0485秒） [XML]
IEnumerable vs List - What to Use? How do they work?
...some doubts over how Enumerators work, and LINQ. Consider these two simple selects:
10 Answers
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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...
app-release-unsigned.apk is not signed
...ettings.
Go to Signing Tab. Add a signing config and fill in information. Select your keychain as well.
Go to Build Type tab. Select release mode and set:
-Debuggable to true.
-Signing Config to the config. (The one you just created).
Sync your gradle. Enjoy!
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Is there a way to view past mysql queries with phpmyadmin?
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To view the past queries simply run this query in phpMyAdmin.
SELECT * FROM `general_log`
if it is not enabled, run the following two queries before running it.
SET GLOBAL log_output = 'TABLE';
SET GLOBAL general_log = 'ON';
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How to allow only one radio button to be checked?
... set "groups" of radio buttons, only one radio button in each group can be selected at one time and selecting other will clear the previous selection. :)
– Shadow Wizard is Ear For You
Mar 24 '11 at 13:02
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Why do you need to create a cursor when querying a sqlite database?
...les traversal over the records in a database". For example c.execute('''SELECT * FROM users''') returns an iterator that you can call fetchall() on (or another cursor method). Some SQL queries return empty iterators, but that should be expected, not surprising.
– Powers
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Remove all breakpoints in IntelliJ IDEA
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Ctrl+Shift+F8
is using for removing all breakpoints.
Select upper breakpoint -> Ctrl+Shift+End -> Remove
On Mac Os use this:
Cmd + Shift + (Fn) + F8 on Mac OS
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How do I quickly rename a MySQL database (change schema name)?
...y some developers. phpMyAdmin has an operation for this.
From phpMyAdmin, select the database you want to select. In the tabs there's one called Operations, go to the rename section. That's all.
It does, as many suggested, create a new database with the new name, dump all tables of the old databas...
Xcode 4 - build output directory
... are placed somewhere in ~/Library/Developer/ugly_path/... . I can't even select "show in finder" on my products. It is the same for a simple C project, Foundation tool and even Cocoa bundle. A Debugging works fine.
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Get spinner selected items text?
How to get spinner selected item's text?
13 Answers
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