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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...
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...
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...
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 ...
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)
...
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...
Use gulp to select and move directories and their files
... },
onDemand: true,
discardSelector: ".discard-answer"
,immediatelyShowMarkdownHelp:true,enableSnippets:true
});
}
});
...
How to format numbers as currency string?
...ode with a bit of comments added and some minor changes:
/*
decimal_sep: character used as deciaml separtor, it defaults to '.' when omitted
thousands_sep: char used as thousands separator, it defaults to ',' when omitted
*/
Number.prototype.toMoney = function(decimals, decimal_sep, thousands_sep)...