大约有 41,000 项符合查询结果(耗时:0.0572秒) [XML]
Show constraints on tables command
...
Simply query the INFORMATION_SCHEMA:
USE INFORMATION_SCHEMA;
SELECT TABLE_NAME,
COLUMN_NAME,
CONSTRAINT_NAME,
REFERENCED_TABLE_NAME,
REFERENCED_COLUMN_NAME
FROM KEY_COLUMN_USAGE
WHERE TABLE_SCHEMA = "<your_database_name>"
AND TABLE_NAME = "<y...
Why does changing the returned variable in a finally block not change the return value?
...le s", you set s to refer to the inlined String, not altering the inherent char buffer of the s object to change to "override variable s".
You put a reference to the s on the stack to return to the calling code. Afterwards (when the finally block runs), altering the reference should not do anything ...
foreach with index [duplicate]
...
You can do the following
foreach (var it in someCollection.Select((x, i) => new { Value = x, Index = i }) )
{
if (it.Index > SomeNumber) //
}
This will create an anonymous type value for every entry in the collection. It will have two properties
Value: with the ori...
The difference between bracket [ ] and double bracket [[ ]] for accessing the elements of a list or
...urn the ith sequential element of x.
For lists, one generally uses [[ to select any single element, whereas [ returns a list of the selected elements.
The [[ form allows only a single element to be selected using integer or character indices, whereas [ allows indexing by vectors. Note though tha...
Fragment onCreateView and onActivityCreated called twice
....getFragmentManager().findFragmentByTag(mTag);
}
public void onTabSelected(Tab tab, FragmentTransaction ft) {
if (mFragment == null) {
mFragment = Fragment.instantiate(mActivity, mClass.getName());
ft.replace(android.R.id.content, mFragment, mTag);
} ...
Exit single-user mode
...tabase in MULTI_USER mode.
USE master
GO
DECLARE @kill varchar(max) = '';
SELECT @kill = @kill + 'KILL ' + CONVERT(varchar(10), spid) + '; '
FROM master..sysprocesses
WHERE spid > 50 AND dbid = DB_ID('<Your_DB_Name>')
EXEC(@kill);
GO
SET DEADLOCK_PRIORITY HIGH
ALTER DATABASE [<Your_DB...
How do you check if a certain index exists in a table?
...
You can do it using a straight forward select like this:
SELECT *
FROM sys.indexes
WHERE name='YourIndexName' AND object_id = OBJECT_ID('Schema.YourTableName')
share
|
...
How to get the index of an element in an IEnumerable?
...
extensions with overloads like Select((x, i) => ...) seem to imply that these indexes should exist
– Michael
Mar 19 '14 at 16:05
...
__FILE__, __LINE__, and __FUNCTION__ usage in C++
...docs/papers/2019/p1208r5.pdf
The documentation says:
constexpr const char* function_name() const noexcept;
6 Returns: If this object represents a position in the body of a function,
returns an implementation-defined NTBS that should correspond to the
function name. Otherwise, returns ...
PHP/MySQL insert row then get 'id'
...);
See mysqli_insert_id().
Whatever you do, don't insert and then do a "SELECT MAX(id) FROM mytable". Like you say, it's a race condition and there's no need. mysqli_insert_id() already has this functionality.
share
...
