大约有 41,000 项符合查询结果（耗时：0.0371秒） [XML]
Emacs, switch to previous window
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@phils SHIFT + <keys> meddles with shift selection that is enabled by default from Emacs 23 (shift-selection-mode).
– legends2k
Jul 22 '14 at 12:23
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Accessing an SQLite Database in Swift
...pared statement: \(errmsg)")
}
statement = nil
Prepare new statement for selecting values from table and loop through retrieving the values:
if sqlite3_prepare_v2(db, "select id, name from test", -1, &statement, nil) != SQLITE_OK {
let errmsg = String(cString: sqlite3_errmsg(db)!)
pri...
Unicode, UTF, ASCII, ANSI format differences
...ny other places, it means UTF-8. Properly, Unicode refers to the abstract character set itself, not to any particular encoding.
UTF-16: 2 bytes per "code unit". This is the native format of strings in .NET, and generally in Windows and Java. Values outside the Basic Multilingual Plane (BMP) are enc...
Right query to get the current number of connections in a PostgreSQL DB
...ires aren't equivalent. The equivalent version of the first one would be:
SELECT sum(numbackends) FROM pg_stat_database;
In that case, I would expect that version to be slightly faster than the second one, simply because it has fewer rows to count. But you are not likely going to be able to measu...
How do I get the MAX row with a GROUP BY in LINQ query?
...t by t.SerialNumber
into g
select new
{
SerialNumber = g.Key,
uid = (from t2 in g select t2.uid).Max()
};
}
...
Which timestamp type should I choose in a PostgreSQL database?
...al time zone
test=> SET timezone = 'America/Los_Angeles';
SET
test=> SELECT NOW();
now
-------------------------------
2011-05-27 15:47:58.138995-07
(1 row)
test=> SELECT NOW() AT TIME ZONE 'UTC';
timezone
----------------------------
2011-...
How to convert all text to lowercase in Vim
...ggVGu
Explanation:
gg - goes to first line of text
V - turns on Visual selection, in line mode
G - goes to end of file (at the moment you have whole text selected)
u - lowercase selected area
share
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How does virtual inheritance solve the “diamond” (multiple inheritance) ambiguity?
...virtual void eat(){ std::cout<<"EAT=>D";} };
int main(int argc, char ** argv){
A *a = new D();
a->eat();
delete a;
}
... that way the output is gonna be the correct one: "EAT=>D"
Virtual inheritance only solves the duplication of the grandfather!
BUT you still need ...
How can I tell when a MySQL table was last updated?
...e information_schema database to tell you when another table was updated:
SELECT UPDATE_TIME
FROM information_schema.tables
WHERE TABLE_SCHEMA = 'dbname'
AND TABLE_NAME = 'tabname'
This does of course mean opening a connection to the database.
An alternative option would be to "touch" a ...
How to find and return a duplicate value in array
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@Kalanamith you can get duplicated values using this a.select {|e| a.count(e) > 1}.uniq
– Naveed
Jul 12 '13 at 16:34
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