大约有 46,000 项符合查询结果（耗时：0.0435秒） [XML]
How do you find the row count for all your tables in Postgres
...' AND s.nspname=schema_name
LOOP
RETURN QUERY EXECUTE format('select cast(%L as text),count(*) from %I.%I',
table_name, schema_name, table_name);
END LOOP;
end
$$ language plpgsql;
It takes a schema name as parameter, or public if no parameter is given.
To work with a specific list...
What is the purpose of AsQueryable()?
... change the compile time type of the object to IQueryable. You could just cast it, but by having an AsQueryable method you can take advantage of type inference. This is simply more convenient if the generic argument list is complex, and it is actually necessary if any of the generic arguments are ...
Why are C# 4 optional parameters defined on interface not enforced on implementing class?
...act of that is the behavior you see where you get different results if you cast to an interface.
share
|
improve this answer
|
follow
|
...
SQL Server dynamic PIVOT query?
...
SET @PIVOT_SQL_STRING = 'SELECT top 1 STUFF((SELECT distinct '', '' + CAST(''[''+CONVERT(VARCHAR,'+ @PIVOT_COLUMN+')+'']'' AS VARCHAR(50)) [text()]
FROM '+@TABLE+'
WHERE ISNULL('+@PIVOT_COLUMN+','''') <> ''''
...
How to check if PHP array is associative or sequential?
...
@ARW "PHP seems to cast everything to an int in an array definition if it can." - yep, that's exactly what happens. The biggest WTF is that it even does this to floats; if you try var_dump([1.2 => 'foo', 1.5 => 'bar']); you'll discover th...
Why are C# interface methods not declared abstract or virtual?
...he class' v-table, each slot has a pointer to one of the virtual methods. Casting an object to an interface type generates a pointer to the section of the table that implements the interface methods. The client code that uses the interface reference now sees the first interface method pointer at o...
Why functional languages? [closed]
...heard what my co-worker said to a Java lecturer after he was introduced to casting for the first time (at this point he only knew Haskell) - "What?! You mean you've got something and you don't KNOW what type it is?!"
– Jacob Stanley
Aug 27 '09 at 13:56
...
Is the “struct hack” technically undefined behavior?
...instead of explicitly adding the offset to the pointer returned by malloc, cast to char *, is irrelevant.
Technically, p->s[0] is the single element of the char array inside the struct, the next few elements (e.g. p->s[1] through p->s[3]) are likely padding bytes inside the struct, which c...
Why is Multiple Inheritance not allowed in Java or C#?
...s a lot of complexity into the
implementation. This complexity
impacts casting, layout, dispatch,
field access, serialization, identity
comparisons, verifiability,
reflection, generics, and probably
lots of other places.
You can read the full article here.
For Java, you can read th...
What is the difference between char s[] and char *s?
...
static char __unnamed[] = "abc";
char *c = __unnamed;
Note the implicit cast from char[] to char *, which is always legal.
Then if you modify c[0], you also modify __unnamed, which is UB.
This is documented at 6.4.5 "String literals":
5 In translation phase 7, a byte or code of value zero i...