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SELECT DISTINCT on one column
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leave out "AS" for oracle -> ...WHERE SKU LIKE 'FOO%') a WHERE a.RowNumber = 1
– Andre Nel
Jun 21 '17 at 11:46
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Create unique constraint with null columns
...mplementing the desired constraint.
Possible drawbacks: you cannot have a foreign key referencing (user_id, menu_id, recipe_id), you cannot base CLUSTER on a partial index, and queries without a matching WHERE condition cannot use the partial index. (It seems unlikely you'd want a FK reference thre...
What's the $unwind operator in MongoDB?
...ts, joins, etc. from your mind. The way that it stores your data is in the form of documents and collections, which allows for a dynamic means of adding and obtaining the data from your storage locations.
That being said, in order to understand the concept behind the $unwind parameter, you first mu...
Using SSH keys inside docker container
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It's a harder problem if you need to use SSH at build time. For example if you're using git clone, or in my case pip and npm to download from a private repository.
The solution I found is to add your keys using the --build-arg flag. Then you can use the new experimental --squash comm...
Javascript Equivalent to C# LINQ Select
...uggest that you stick with the jQuery method.
If you prefer the other one for some reason you could always add a polyfill for old browser support.
You can always add custom methods to the array prototype as well:
Array.prototype.select = function(expr){
var arr = this;
//do custom stuff
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Database Design for Tagging
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About ANDing: It sounds like you are looking for the "relational division" operation. This article covers relational division in concise and yet comprehendible way.
About performance: A bitmap-based approach intuitively sounds like it will suit the situation well. Howe...
How to use WHERE IN with Doctrine 2
... that will be important to anyone running into this same issue and looking for a solution.
From the original post, the following line of code:
$qb->add('where', $qb->expr()->in('r.winner', array('?1')));
Wrapping the named parameter as an array causes the bound parameter number issue. B...
android.widget.Switch - on/off event listener?
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But when you put the on a fragment for example, that thing always fires whenever you revisit the fragment if you set the switch to On.
– klutch
Sep 23 '16 at 8:04
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Fragment is not being replaced but put on top of the previous one
...tainer that you added the first fragment to.
You can refer to this link for more details.
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What's the proper value for a checked attribute of an HTML checkbox?
We all know how to form a checkbox input in HTML:
8 Answers
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