大约有 41,000 项符合查询结果（耗时：0.0381秒） [XML]
When to use EntityManager.find() vs EntityManager.getReference() with JPA
... }
}
If i call find method, JPA provider, behind the scenes, will call
SELECT NAME, AGE FROM PERSON WHERE PERSON_ID = ?
UPDATE PERSON SET AGE = ? WHERE PERSON_ID = ?
If i call getReference method, JPA provider, behind the scenes, will call
UPDATE PERSON SET AGE = ? WHERE PERSON_ID = ?
And ...
How to for each the hashmap? [duplicate]
...I did too, in case it helps someone else :
HashMap<String, HashMap> selects = new HashMap<String, HashMap>();
for(Map.Entry<String, HashMap> entry : selects.entrySet()) {
String key = entry.getKey();
HashMap value = entry.getValue();
// do what you have to do here
...
LINQ to SQL - Left Outer Join with multiple join conditions
...g.Where(f => f.otherid == 17).DefaultIfEmpty()
where p.companyid == 100
select f.value
Or you could use a subquery:
from p in context.Periods
join f in context.Facts on p.id equals f.periodid into fg
from fgi in (from f in fg
where f.otherid == 17
select f).DefaultIfE...
Eclipse copy/paste entire line keyboard shortcut
...
Ctrl-Alt-Down: copies current line or selected lines to below
Ctrl-Alt-Up:: copies current line or selected lines to above
Ctrl-Shift-L: brings up a List of shortcut keys
See Windows/Preference->General->Keys.
...
LINQ - Full Outer Join
...rst.ID equals last.ID into temp
from last in temp.DefaultIfEmpty()
select new
{
first.ID,
FirstName = first.Name,
LastName = last?.Name,
};
var rightOuterJoin =
from last in lastNames
join first in firstNames on last.ID equals first.ID into temp
fr...
Dealing with commas in a CSV file
... s = s.Replace( QUOTE, ESCAPED_QUOTE );
if ( s.IndexOfAny( CHARACTERS_THAT_MUST_BE_QUOTED ) > -1 )
s = QUOTE + s + QUOTE;
return s;
}
public static string Unescape( string s )
{
if ( s.StartsWith( QUOTE ) && s.EndsWith( QUOTE ) )
...
Use JNI instead of JNA to call native code?
...g to the Java standard output:
native "C++" void printHello() {
const char* helloWorld = "Hello, World!";
`System.out.println(#$(helloWorld));`
}
JANET then translates the backtick-embedded Java into the appropriate JNI calls.
...
What is a C++ delegate?
...lic:
virtual void Fn( int i )
{
}
};
int main( int /*argc*/, char * /*argv*/ )
{
A a;
CCallback<A> cbk( a, &A::Fn );
cbk.Execute( 3 );
}
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How to select a CRAN mirror in R
...
Repository selection screen cannot be shown on your system (OS X), since OS X no longer includes X11. R tries to show you the prompt through X11. Install X11 from http://xquartz.macosforge.org/landing/. Then run the install command. The...
jQuery - getting custom attribute from selected option
...
You're adding the event handler to the <select> element.
Therefore, $(this) will be the dropdown itself, not the selected <option>.
You need to find the selected <option>, like this:
var option = $('option:selected', this).attr('mytag');
...