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React JSX: selecting “selected” on selected option
In a React component for a <select> menu, I need to set the selected attribute on the option that reflects the application state.
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Removing rounded corners from a element in Chrome/Webkit
...sheet for Chrome gives a border-radius of 5px to all the corners of a <select> element. I've tried getting rid of this by applying a radius of 0px through my external stylesheet, as well inline on the element itself; I've tried both border-radius:0px and -webkit-border-radius:0px; and I...
Simplest way to do a recursive self-join?
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WITH q AS
(
SELECT *
FROM mytable
WHERE ParentID IS NULL -- this condition defines the ultimate ancestors in your chain, change it as appropriate
UNION ALL
SELECT m.*
FROM mytable m
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Is there any difference between GROUP BY and DISTINCT
...CT and distinct by UNION cause an oracle error, but GROUP BY worked; I was selecting only 1 column from a view and not using any aggregation; I'm still baffled why it required it, but it does confirm there is some difference in the execution. As others point out, it also lets you GROUP BY columns no...
How do I do top 1 in Oracle?
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If you want just a first selected row, you can:
select fname from MyTbl where rownum = 1
You can also use analytic functions to order and take the top x:
select max(fname) over (rank() order by some_factor) from MyTbl
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How can I select rows with most recent timestamp for each key value?
...r data. Each row has a sensor id, a timestamp, and other fields. I want to select a single row with latest timestamp for each sensor, including some of the other fields.
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How to search a string in multiple files and return the names of files in Powershell?
...location of the files that contain your pattern:
Get-ChildItem -Recurse | Select-String "dummy" -List | Select Path
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Fastest way to determine if record exists
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SELECT TOP 1 products.id FROM products WHERE products.id = ?; will outperform all of your suggestions as it will terminate execution after it finds the first record.
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How to Join to first row
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SELECT Orders.OrderNumber, LineItems.Quantity, LineItems.Description
FROM Orders
JOIN LineItems
ON LineItems.LineItemGUID =
(
SELECT TOP 1 LineItemGUID
FROM LineItems
W...
Vim search and replace selected text
Let's say we have a text, and I enter visual mode and select some text. How do I quickly do a search for the highlighted text and replace it with something else?
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