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Delete sql rows where IDs do not have a match from another table
...HERE f.id IS NULL
Using NOT EXISTS:
DELETE FROM BLOB
WHERE NOT EXISTS(SELECT NULL
FROM FILES f
WHERE f.id = fileid)
Using NOT IN:
DELETE FROM BLOB
WHERE fileid NOT IN (SELECT f.id
FROM FILES f)
Warning
Whenever possible, per...
Handling colon in element ID with jQuery
.../ Timing
have a look at this jsbin which tests and compares the speed of selection methods of IDs with colons
you need to open your firebug console to get the results.
I tested it with firefox 10 and jquery 1.7.2
basically I did a select 10'000 times of a div with a colon in the id - with the d...
How to insert a value that contains an apostrophe (single quote)?
... 'O''Brien')
/\
right here
The same applies to SELECT queries:
SELECT First, Last FROM Person WHERE Last = 'O''Brien'
The apostrophe, or single quote, is a special character in SQL that specifies the beginning and end of string data. This means that to use it as part...
How to cut an entire line in vim and paste it?
...
Pressing Shift+v would select that entire line and pressing d would delete it.
You can also use dd, which is does not require you to enter visual mode.
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Real differences between “java -server” and “java -client”?
...ient option is ignored for many years.
See Windows java command:
-client
Selects the Java HotSpot Client VM.
A 64-bit capable JDK currently ignores this option and instead uses the Java Hotspot Server VM.
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How to get the date from jQuery UI datepicker
...tepicker_id').datepicker('getDate');
if (jsDate !== null) { // if any date selected in datepicker
jsDate instanceof Date; // -> true
jsDate.getDate();
jsDate.getMonth();
jsDate.getFullYear();
}
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Taking screenshot on Emulator from Android Studio
...or:
Just click 3 "Take Screenshot". Standard location is the desktop.
Or
Select "More"
Under "Settings", specify the location for your screenshot
Take your screenshot
UPDATE 22/07/2020
If you keep the emulator in Android Studio as possible since Android Studio 4.1 click here to save the screensho...
How do I convert an integer to string as part of a PostgreSQL query?
...o 15 digits, you'll meed to cast to an 64 bit (8-byte) integer. Try this:
SELECT * FROM table
WHERE myint = mytext::int8
The :: cast operator is historical but convenient. Postgres also conforms to the SQL standard syntax
myint = cast ( mytext as int8)
If you have literal text you want to c...
Random row from Linq to Sql
...ere row.IsActive // your filter
orderby ctx.Random()
select row).FirstOrDefault();
Note that this is only suitable for small-to-mid-size tables; for huge tables, it will have a performance impact at the server, and it will be more efficient to find the number of rows (Count),...
Nesting await in Parallel.ForEach
..., "2", "3", "4", "5", "6", "7", "8", "9", "10" };
var customerTasks = ids.Select(i =>
{
ICustomerRepo repo = new CustomerRepo();
return repo.GetCustomer(i);
});
var customers = await Task.WhenAll(customerTasks);
foreach (var customer in customers)
{
Console.WriteLine(customer.ID);...