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mysql - how many columns is too many?
...every column to be returned by every query is perfectly normal; that's why SELECT statement lets you explicitly name the columns you need.
As a general rule, your table structure should reflect your domain model; if you really do have 70 (100, what have you) attributes that belong to the same entit...
Faster s3 bucket duplication
...
If you don't mind using the AWS console, you can:
Select all of the files/folders in the first bucket
Click Actions > Copy
Create a new bucket and select it
Click Actions > Paste
It's still fairly slow, but you can leave it alone and let it do its thing.
...
Add shadow to custom shape on Android
...;/shape>
</item>
</layer-list>
Then you should have a selector with diferent versions of the button, something like:
<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
<item android:drawable="@drawabl...
Writing data into CSV file in C#
...re the values
var allLines = (from trade in proposedTrades
select new object[]
{
trade.TradeType.ToString(),
trade.AccountReference,
trade.SecurityCodeType.ToString(),
trade.SecurityC...
A weighted version of random.choice
...dom.choice (each element in the list has a different probability for being selected). This is what I came up with:
25 Answ...
Find text string using jQuery?
...undin = $('*:contains("I am a simple string")');
});
</script>
The selector above selects any element that contains the target string. The foundin will be a jQuery object that contains any matched element. See the API information at: https://api.jquery.com/contains-selector/
One thing to ...
chrome undo the action of “prevent this page from creating additional dialogs”
...correct answer is: YES, there is a better way.
Right click on the tab and select "Duplicate", then close the original tab if you wish.
Alerting is re-enabled in the duplicate.
The duplicate tab seems to recreate the running state of the original tab so you can just continue where you were.
...
Rails Object to hash
...
Works with joins and select, Person.joins(:address).select("addresses.street, persons.name").find_by_id(id).attributes, will return { street: "", name: "" }
– fangxing
Jun 15 '17 at 2:29
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Is there any way to delete local commits in Mercurial?
...ust activate the extension "strip" in:
File/Settings/Extensions/
Select strip
Then select the bottom revision from where you want to start striping, by doing right click on it, and selecting:
Modify history
Strip
Just like this:
In this example it will erase from the ...
Converting an array of objects to ActiveRecord::Relation
...e clause will generate a SQL statement with IN that looks something like:
SELECT .... WHERE `my_models`.id IN (2, 3, 4, 6, ....
Keep in mind that the ordering of the array will be lost - But since your objective is only to run a class method on the collection of these objects, I assume it won't b...