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What is the difference between NULL, '\0' and 0?
...xDEADBEEF)
as these are seen by a compiler as normal comparisons.
Null Characters
'\0' is defined to be a null character - that is a character with all bits set to zero. This has nothing to do with pointers. However you may see something similar to this code:
if (!*string_pointer)
checks if ...
__FILE__ macro shows full path
...lity tool would be careful to split file names at both slash and backslash characters to avoid any problems for folks that do manage to use /.
– RBerteig
Sep 13 '12 at 20:53
...
Is it possible for git-merge to ignore line-ending differences?
...e.autoCRLF=false
Test that, when two lines are identical (but their eol chars), both DiffMerge or KDiff3 will ignore those line during a merge.
DOS script (note: the dos2unix command comes from here, and is used to simulate a Unix eol-style. That command has been copied in the directory mentione...
Simple way to convert datarow array to datatable
...For .Net Framework 3.5+
DataTable dt = new DataTable();
DataRow[] dr = dt.Select("Your string");
DataTable dt1 = dr.CopyToDataTable();
But if there is no rows in the array, it can cause the errors such as The source contains no DataRows. Therefore, if you decide to use this method CopyToDataTable...
Add primary key to existing table
...PMID)
edit:
you can find the constraint name by using the query below:
select OBJECT_NAME(OBJECT_ID) AS NameofConstraint
FROM sys.objects
where OBJECT_NAME(parent_object_id)='Persion'
and type_desc LIKE '%CONSTRAINT'
sh...
Is having an 'OR' in an INNER JOIN condition a bad idea?
... a MERGE JOIN.
It can be expressed as a concatenation of two resultsets:
SELECT *
FROM maintable m
JOIN othertable o
ON o.parentId = m.id
UNION
SELECT *
FROM maintable m
JOIN othertable o
ON o.id = m.parentId
, each of them being an equijoin, however, SQL Server's optimiz...
Parse config files, environment, and command-line arguments, to get a single collection of options
...because users will only have to learn one syntax.) Setting fromfile_prefix_chars to, for example, @, makes it so that,
my_prog --foo=bar
is equivalent to
my_prog @baz.conf
if @baz.conf is,
--foo
bar
You can even have your code look for foo.conf automatically by modifying argv
if os.path.e...
Getting attribute using XPath
...e), for
the first element?
Use:
/*/book[1]/title/@lang
This means:
Select the lang attribute of the title element that is a child of the first book child of the top element of the XML document.
To get just the string value of this attribute use the standard XPath function string():
string(...
Cannot use a CONTAINS or FREETEXT predicate on table or indexed view because it is not full-text ind
...
use AdventureWorks
create fulltext catalog FullTextCatalog as default
select *
from sys.fulltext_catalogs
Create full-text search index.
create fulltext index on Production.ProductDescription(Description)
key index PK_ProductDescription_ProductDescriptionID
Before you create the index, m...
Laravel Eloquent groupBy() AND also return count of each group
...working for me:
$user_info = DB::table('usermetas')
->select('browser', DB::raw('count(*) as total'))
->groupBy('browser')
->get();
share
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