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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 ...
Should I URL-encode POST data?
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General Answer
The general answer to your question is that it depends. And you get to decide by specifying what your "Content-Type" is in the HTTP headers.
A value of "application/x-www-form-urlencoded" means that your POST body will need to be URL encoded just like a GET parameter string. A va...
Ideal way to cancel an executing AsyncTask
I am running remote audio-file-fetching and audio file playback operations in a background thread using AsyncTask . A Cancellable progress bar is shown for the time the fetch operation runs.
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A generic error occurred in GDI+, JPEG Image to MemoryStream
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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...
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...
how to install gcc on windows 7 machine?
I have MinGW on my windows 7 machine. I wish to install and use complete gcc for C compiler. I found there is no single pre-compiled ready-made installation file for this purpose. I checked the following page : http://gcc.gnu.org/install/
It is difficult and I find it above my level of understandi...
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...
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 ...
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.
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Shortcut to create properties in Visual Studio?
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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...