大约有 41,000 项符合查询结果（耗时：0.0393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...
How to call Android contacts list?
...TION_PICK on the People.CONTENT_URI, then return to this Activity when the selection is made (or canceled).
startActivityForResult(intent, PICK_CONTACT);
3. Listening for the Result
Also in your Activity, override the onActivityResult method to listen for the return from the 'select a contact' A...
How to shuffle a std::vector?
...zer.h"
#include <iostream>
using namespace std;
int main (int argc, char* argv[]) {
vector<int> v;
v.push_back(1);v.push_back(2);v.push_back(3);v.push_back(4);v.push_back(5);
v.push_back(6);v.push_back(7);v.push_back(8);v.push_back(9);v.push_back(10);
Randomizer::get_in...
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
|
...
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 to update column with null value
...Hello');
UPDATE your_table
SET your_column = NULL
WHERE some_id = 1;
SELECT * FROM your_table WHERE your_column IS NULL;
+---------+-------------+
| some_id | your_column |
+---------+-------------+
| 1 | NULL |
+---------+-------------+
1 row in set (0.00 sec)
...
Correct format specifier to print pointer or address?
...to void. The value of the pointer is
converted to a sequence of printing characters, in an implementation-defined
manner.
(In C11 — ISO/IEC 9899:2011 — the information is in §7.21.6.1 ¶8.)
On some platforms, that will include a leading 0x and on others it won't, and the letters could be...
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...
What is meant by Resource Acquisition is Initialization (RAII)?
...s piece of code:
void fn(const std::string& str)
{
std::vector<char> vec;
for (auto c : str)
vec.push_back(c);
// do something
}
when you create a vector and you push elements to it, you don't care about allocating and deallocating such elements. The vector uses new ...
Use gulp to select and move directories and their files
... },
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...