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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;
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How to get href value using jQuery?
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answered Jan 20 '10 at 1:38
GarethGareth
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How to redirect the output of an application in background to /dev/null
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How to make an element in XML schema optional?
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How to get a vertical geom_vline to an x-axis of class date?
... a time series from and would like to draw a vertical line for years 1998, 2005 and 2010 for example. I tried with ggplot and qplot syntax, but still I either see no vertical line at all or the vertical line is drawn at the very first vertical grid and the whole series is shifted somewhat strang...
Regular expression for exact match of a string
...tch two passwords with regular expression. For example I have two inputs "123456" and "1234567" then the result should be not match (false). And when I have entered "123456" and "123456" then the result should be match (true).
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Differences in auto-unboxing between Java 6 vs Java 7
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How do I access the host machine itself from the iPhone simulator
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Get ffmpeg information in friendly way
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A bit late, but perhaps still relevant to someone..
ffprobe is indeed an excellent way to go....
Using Position Relative/Absolute within a TD?
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This is because according to CSS 2.1, the effect of position: relative on table elements is undefined. Illustrative of this, position: relative has the desired effect on Chrome 13, but not on Firefox 4. Your solution here is to add a div around your content ...