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Is SQL or even TSQL Turing Complete?
...e true programming languages, so that's kinda cheating).
In this set of slides Andrew Gierth proves that with CTE and Windowing SQL is Turing Complete, by constructing a cyclic tag system, which has been proved to be Turing Complete. The CTE feature is the important part however -- it allows you to...
UPDATE multiple tables in MySQL using LEFT JOIN
...
UPDATE t1
LEFT JOIN
t2
ON t2.id = t1.id
SET t1.col1 = newvalue
WHERE t2.id IS NULL
Note that for a SELECT it would be more efficient to use NOT IN / NOT EXISTS syntax:
SELECT t1.*
FROM t1
WHERE t1.id NOT IN
(
SELECT id
...
Print Current Mercurial Revision Hash?
...
Try:
hg id -i
Example:
$ hg id -i
adc56745e928
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Change the name of the :id parameter in Routing resources for Rails
...he post is https://thoughtbot.com/blog/rails-patch-change-the-name-of-the-id-parameter-in
5 Answers
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SQL query for finding records where count > 1
I have a table named PAYMENT . Within this table I have a user ID, an account number, a ZIP code and a date. I would like to find all records for all users that have more than one payment per day with the same account number.
...
Yii2 data provider default sorting
...nk there's proper solution. Configure the yii\data\Sort object:
$dataProvider = new ActiveDataProvider([
'query' => $query,
'sort'=> ['defaultOrder' => ['topic_order' => SORT_ASC]],
]);
Official doc link
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Is there a “not in” operator in JavaScript for checking object properties?
... portion...
Just negate your condition, and you'll get the else logic inside the if:
if (!(id in tutorTimes)) { ... }
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How to get a Docker container's IP address from the host
...{range .NetworkSettings.Networks}}{{.IPAddress}}{{end}}' container_name_or_id
Old Docker client syntax is:
docker inspect --format '{{ .NetworkSettings.IPAddress }}' container_name_or_id
These commands will return the Docker container's IP address.
As mentioned in the comments: if you are on W...
Share application “link” in Android
...ectly go to the install screen of market place for instance. All I can provide them with is a web link or some text.
In other words I am looking for a very direct way for android users to have my app installed.
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How to return a file using Web API?
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Better to return HttpResponseMessage with StreamContent inside of it.
Here is example:
public HttpResponseMessage GetFile(string id)
{
if (String.IsNullOrEmpty(id))
return Request.CreateResponse(HttpStatusCode.BadRequest);
string fileName;
string localFilePath;...