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jQuery get selected option value (not the text, but the attribute 'value')
...
04/2020: Corrected old answer
Use :selected psuedo selector on the selected options and then use the .val function to get the value of the option.
$('select[name=selector] option').filter(':selected').val()
Side note: Using filter is better then using :sele...
IN clause and placeholders
...mes = { "name1", "name2" }; // do whatever is needed first
String query = "SELECT * FROM table"
+ " WHERE name IN (" + makePlaceholders(names.length) + ")";
Cursor cursor = mDb.rawQuery(query, names);
Just make sure to pass exactly as many values as places. The default maximum limit of host pa...
What is the difference between JOIN and UNION?
...t -- completely different operations. Trivial example of UNION:
mysql> SELECT 23 AS bah
-> UNION
-> SELECT 45 AS bah;
+-----+
| bah |
+-----+
| 23 |
| 45 |
+-----+
2 rows in set (0.00 sec)
similary trivial example of JOIN:
mysql> SELECT * FROM
-> (SELECT 23 AS bah...
Should MySQL have its timezone set to UTC?
...the timezone will not change the stored datetime or
timestamp, but it will select a different datetime from
timestamp columns
Warning! UTC has leap seconds, these look like '2012-06-30 23:59:60' and can
be added randomly, with 6 months prior notice, due to the slowing of
the earths rotation
GMT con...
PostgreSQL function for last inserted ID
...e:
INSERT INTO persons (lastname,firstname) VALUES ('Smith', 'John');
SELECT currval('persons_id_seq');
The name of the sequence must be known, it's really arbitrary; in this example we assume that the table persons has an id column created with the SERIAL pseudo-type. To avoid relying on thi...
Measure the time it takes to execute a t-sql query
... to just grab the current date and time.
In SQL Server Management Studio
SELECT GETDATE();
SELECT /* query one */ 1 ;
SELECT GETDATE();
SELECT /* query two */ 2 ;
SELECT GETDATE();
To calculate elapsed times, you could grab those date values into variables, and use the DATEDIFF function:
DECL...
Remove an entire column from a data.frame in R
...=4:6)
to remove just the a column you could do
Data <- subset( Data, select = -a )
and to remove the b and d columns you could do
Data <- subset( Data, select = -c(d, b ) )
You can remove all columns between d and b with:
Data <- subset( Data, select = -c( d : b )
As I said above...
UITableViewCell subview disappears when cell is selected
I'm implementing a color-chooser table view where the user can select amongst, say, 10 colors (depends on the product). The user can also select other options (like hard drive capacity, ...).
...
How can I do SELECT UNIQUE with LINQ?
...e.MainTable
where dbo.Property == true
select dbo.Color.Name).Distinct().OrderBy(name=>name);
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Javascript Equivalent to C# LINQ Select
...always add custom methods to the array prototype as well:
Array.prototype.select = function(expr){
var arr = this;
//do custom stuff
return arr.map(expr); //or $.map(expr);
};
var ids = this.fruits.select(function(v){
return v.Id;
});
An extended version that uses the function ...