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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...
jQuery: checking if the value of a field is null (empty)
... be null, it's always a string value. this isn't entirely true. I've got a select containing no options. When I perform .val() on this it returns null. Jquery 1.7.2
– Liam
Jan 14 '13 at 11:07
...
How to get everything after a certain character?
...+ 1);
echo $whatIWant;
If you also want to check if the underscore character (_) exists in your string before trying to get it, you can use the following:
if (($pos = strpos($data, "_")) !== FALSE) {
$whatIWant = substr($data, $pos+1);
}
...
AngularJs: How to check for changes in file input fields?
...er="form-cntlr">
<form>
<button ng-click="selectFile()">Upload Your File</button>
<input type="file" style="display:none"
id="file" name='file' onchange="angular.element(this).scope().fileNameChanged(this)" />
<...
Binding a WPF ComboBox to a custom list
I have a ComboBox that doesn't seem to update the SelectedItem/SelectedValue.
4 Answers
...
What's the fastest way to do a bulk insert into Postgres?
...200, 300]),
UNNEST(ARRAY['a', 'b', 'c'])
);
without VALUES using subselect with additional existance check:
INSERT INTO tablename (fieldname1, fieldname2, fieldname3)
SELECT * FROM (
SELECT UNNEST(ARRAY[1, 2, 3]),
UNNEST(ARRAY[100, 200, 300]),
UNNEST(ARRAY['a', 'b...
Why use the SQL Server 2008 geography data type?
...tance < 500 * 1609.344
orderby distance
select f;
return q1.FirstOrDefault();
}
Then there is a very good reason to use Geography.
Explanation of spatial within Entity Framework.
Updated with Creating High Performance Spatial Databases
As I noted on Noe...
Need to handle uncaught exception and send log file
...pp version: " + (info == null ? "(null)" : info.versionCode) + "\n");
char[] buffer = new char[10000];
do
{
int n = reader.read (buffer, 0, buffer.length);
if (n == -1)
break;
writer.write (buffer, 0, n);
} while (true);
reader.close();
writer.clo...
Preventing an image from being draggable or selectable without using JS
Does anyone know of a way to make an image not draggable and not selectable -- at the same time -- in Firefox, without resorting to Javascript? Seems trivial, but here's the issue:
...
HTML5: number input type that takes only integers?
...f chrome. It does not allow letters to be typed, but it does allow special characters to be inserted.
– Malavos
Feb 21 '15 at 21:39
3
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