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postgresql COUNT(DISTINCT …) very slow
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323
You can use this:
SELECT COUNT(*) FROM (SELECT DISTINCT column_name FROM table_name) AS temp;...
onTouchListener warning: onTouch should call View#performClick when a click is detected
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answered Jul 13 '19 at 20:32
yoAlex5yoAlex5
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How do I make many-to-many field optional in Django?
...000/svg\"\u003e\u003cpath d=\"M46.1709 9.17788C46.1709 8.26454 46.2665 7.94324 47.1084 7.58816C47.4091 7.46349 47.7169 7.36433 48.0099 7.26993C48.9099 6.97997 49.672 6.73443 49.672 5.93063C49.672 5.22043 48.9832 4.61182 48.1414 4.61182C47.4335 4.61182 46.7256 4.91628 46.0943 5.50789C45.7307 4.9328 4...
split string in to 2 based on last occurrence of a separator
...000/svg\"\u003e\u003cpath d=\"M46.1709 9.17788C46.1709 8.26454 46.2665 7.94324 47.1084 7.58816C47.4091 7.46349 47.7169 7.36433 48.0099 7.26993C48.9099 6.97997 49.672 6.73443 49.672 5.93063C49.672 5.22043 48.9832 4.61182 48.1414 4.61182C47.4335 4.61182 46.7256 4.91628 46.0943 5.50789C45.7307 4.9328 4...
“Automatic” vs “Automatic (Delayed start)”
...000/svg\"\u003e\u003cpath d=\"M46.1709 9.17788C46.1709 8.26454 46.2665 7.94324 47.1084 7.58816C47.4091 7.46349 47.7169 7.36433 48.0099 7.26993C48.9099 6.97997 49.672 6.73443 49.672 5.93063C49.672 5.22043 48.9832 4.61182 48.1414 4.61182C47.4335 4.61182 46.7256 4.91628 46.0943 5.50789C45.7307 4.9328 4...
Passing two command parameters using a WPF binding
...the view?
– JasonD
Aug 29 '09 at 18:32
@Jason: you can do it either way. That is, have the view push changes back to t...
How do you skip a unit test in Django?
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Razzi Abuissa
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answered Jul 8 '13 at 5:25
Ray ToalRay Toal
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What does extern inline do?
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Jo So
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answered Oct 19 '08 at 15:35
puetzkpuetzk
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Pass a data.frame column name to a function
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> new_column3(dat,z,x*y)
x y z
1 1 5 5
2 2 6 12
3 3 7 21
4 4 8 32
So the short answer is basically: pass data.frame column names as strings and use [[ to select single columns. Only start delving into eval, substitute, etc. if you really know what you're doing.
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Is it okay to use now?
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animuson♦animuson
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