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Optimise PostgreSQL for fast testing
.... For example, PostgreSQL 9.2 significantly improves the speed of TRUNCATE and of course adds index-only scans. Even minor releases should always be followed; see the version policy.
Don'ts
Do NOT put a tablespace on a RAMdisk or other non-durable storage.
If you lose a tablespace the whole datab...
A generic error occurred in GDI+, JPEG Image to MemoryStream
...
OK I seem to have found the cause just by sheer luck and its nothing wrong with that particular method, it's further back up the call stack.
Earlier I resize the image and as part of that method I return the resized object as follows. I have inserted two calls to the above met...
Best way to test if a row exists in a MySQL table
...ou could also try EXISTS:
SELECT EXISTS(SELECT * FROM table1 WHERE ...)
and per the documentation, you can SELECT anything.
Traditionally, an EXISTS subquery starts with SELECT *, but it could
begin with SELECT 5 or SELECT column1 or anything at all. MySQL
ignores the SELECT list in such ...
Running shell command and capturing the output
I want to write a function that will execute a shell command and return its output as a string , no matter, is it an error or success message. I just want to get the same result that I would have gotten with the command line.
...
Computed / calculated / virtual / derived columns in PostgreSQL
... Postgres 11 generated columns are not supported - as defined in the SQL standard and implemented by some RDBMS including DB2, MySQL and Oracle. Nor the similar "computed columns" of SQL Server.
STORED generated columns are introduced with Postgres 12. Trivial example:
CREATE TABLE tbl (
int1 ...
How can you use an object's property in a double-quoted string?
... # yields "abc.Length"
"$($bar.Length)" # yields "3"
PowerShell only expands variables in those cases, nothing more. To force evaluation of more complex expressions, including indexes, properties or even complete calculations, you have to enclose those in the subexpression operator $( ) which cau...
Shortcut to create properties in Visual Studio?
...
You could type "prop" and then press tab twice. That will generate the following.
public TYPE Type { get; set; }
Then you change "TYPE" and "Type":
public string myString {get; set;}
You can also get the full property typing "propfull" and t...
Webfonts or Locally loaded fonts?
...le's offering. It will actually load the smallest format your browser can handle. WOFF offers small file sizes, and your browser supports it, so it's the one you see. WOFF is also fairly widely supported. However, in Opera for example, you'll probably get the TrueType version of the font.
The file ...
Stop Chrome Caching My JS Files
...iles every time so that it reloads it. Is there some sort of .htaccess command I can add or something to make it stop caching?
...
How do I retrieve an HTML element's actual width and height?
... the browser's display (viewport). To do so, I need to calculate the width and height of the <div> element.
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