大约有 41,000 项符合查询结果（耗时：0.0505秒） [XML]
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...
How to compare two colors for similarity/difference
...For posterity, here's the relevant C code:
typedef struct {
unsigned char r, g, b;
} RGB;
double ColourDistance(RGB e1, RGB e2)
{
long rmean = ( (long)e1.r + (long)e2.r ) / 2;
long r = (long)e1.r - (long)e2.r;
long g = (long)e1.g - (long)e2.g;
long b = (long)e1.b - (long)e2.b;...
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(...
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...
Get Specific Columns Using “With()” Function in Laravel Eloquent
... like
Post::with(array('user'=>function($query){
$query->select('id','username');
}))->get();
It will only select id and username from other table. I hope this will help others.
Remember that the primary key (id in this case) needs to be the first param in the
$query->s...
The object 'DF__*' is dependent on column '*' - Changing int to double
...te void DropConstraint()
{
Sql(@"DECLARE @var0 nvarchar(128)
SELECT @var0 = name
FROM sys.default_constraints
WHERE parent_object_id = object_id(N'dbo.MyTable')
AND col_name(parent_object_id, parent_column_id) = 'Rating';
IF @var0 IS NOT NULL
...
Failure [INSTALL_FAILED_ALREADY_EXISTS] when I tried to update my application
...lease variant
Bonus
I set up an alias in my ~/.bash_profile, to make it a 2char command.
alias bi="gradlew && adb install -r exampleApp.apk"
(Short for Build and Install)
share
|
improve th...
Enums and Constants. Which to use when?
...ype. You can change the default from int to any other integral type except char like:
enum LongEnum : long {
foo,
bar,
}
You can cast explicitly from and implicitly to the the base type, which is useful in switch-statements. Beware that one can cast any value of the base type to an enum, ...
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...
How can I find out what FOREIGN KEY constraint references a table in SQL Server?
...
Here it is:
SELECT
OBJECT_NAME(f.parent_object_id) TableName,
COL_NAME(fc.parent_object_id,fc.parent_column_id) ColName
FROM
sys.foreign_keys AS f
INNER JOIN
sys.foreign_key_columns AS fc
ON f.OBJECT_ID = fc.constra...