大约有 40,000 项符合查询结果（耗时：0.0334秒） [XML]
postgresql COUNT(DISTINCT …) very slow
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You can use this:
SELECT COUNT(*) FROM (SELECT DISTINCT column_name FROM table_name) AS temp;
This is much faster than:
COUNT(DISTINCT column_name)
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Ineligible Devices section appeared in Xcode 6.x.x
...6 my devices moved to greyed-out section Ineligible Devices and I can't select them as deploy target:
32 Answers
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SQL query to group by day
...dateadd(DAY,0, datediff(day,0, created)) return '2009-11-02 00:00:00.000'
select sum(amount) as total, dateadd(DAY,0, datediff(day,0, created)) as created
from sales
group by dateadd(DAY,0, datediff(day,0, created))
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How do I use variables in Oracle SQL Developer?
... other stuff didn't work for me, but this did:
define value1 = 'sysdate'
SELECT &&value1 from dual;
Also it's the slickest way presented here, yet.
(If you omit the "define"-part you'll be prompted for that value)
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Copying text with color from Notepad++
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In NPP v6.7.7 you can do this by selecting your text, right clicking on it, select "Plugin commands" and then "Copy text with syntax highlighting".
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Maven2: Best practice for Enterprise Project (EAR file)
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What helped me a lot was to run the Maven archetype:generate goal and select from one of the archetypes, some of which seem to be updated regularly (in particular JBoss seems to be well maintained).
mvn archetype:generate
Hundreds of archetypes appeared in a numbered list from which to selec...
How to disable text selection highlighting
...S standard way to disable the highlighting effect if the user accidentally selects the text?
48 Answers
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Select all elements with “data-” attribute without using jQuery
Using only JavaScript, what is the most efficient way to select all DOM elements that have a certain data- attribute (let's say data-foo ). The elements may be different tag elements.
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MySQL date format DD/MM/YYYY select query?
...ably just want to format the output date? then this is what you are after
SELECT *, DATE_FORMAT(date,'%d/%m/%Y') AS niceDate
FROM table
ORDER BY date DESC
LIMIT 0,14
Or do you actually want to sort by Day before Month before Year?
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How do I get a distinct, ordered list of names from a DataTable using LINQ?
...tainable, you can also split it up into multiple LINQ statements.
First, select your data into a new list, let's call it x1, do a projection if desired
Next, create a distinct list, from x1 into x2, using whatever distinction you require
Finally, create an ordered list, from x2 into x3, sorting by...