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Rails: select unique values from a column
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Model.select(:rating)
Result of this is a collection of Model objects. Not plain ratings. And from uniq's point of view, they are completely different. You can use this:
Model.select(:rating).map(&:rating).uniq
or this (mo...
What is the difference between the states selected, checked and activated in Android?
...below added):
... For example, in a list view with single or multiple selection
enabled, the views in the current selection set are activated. (Um,
yeah, we are deeply sorry about the terminology here.) The activated
state is propagated down to children of the view it is set on.
So here...
Mysql: Select rows from a table that are not in another
How to select all rows in one table that do not appear on another?
8 Answers
8
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getting the ng-object selected with ng-change
Given the following select element
10 Answers
10
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Is there a way to make a DIV unselectable?
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I wrote a simple jQuery extension to disable selection some time back: Disabling Selection in jQuery. You can invoke it through $('.button').disableSelection();
Alternately, using CSS (cross-browser):
.button {
user-select: none;
-moz-user-select: none...
Fast way to discover the row count of a table in PostgreSQL
...in your case.
Instead of getting the exact count (slow with big tables):
SELECT count(*) AS exact_count FROM myschema.mytable;
You get a close estimate like this (extremely fast):
SELECT reltuples::bigint AS estimate FROM pg_class where relname='mytable';
How close the estimate is depends on ...
jQuery - select all text from a textarea
...can I make it so when you click inside a textarea, its entire content gets selected?
6 Answers
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How to select rows that have current day's timestamp?
I am trying to select only today's records from a database table.
9 Answers
9
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Caveats of select/poll vs. epoll reactors in Twisted
...o based apps ) leads me to believe that ePoll is a natural replacement for Select and Poll based networking, especially with Twisted. Which makes me paranoid, its pretty rare for a better technique or methodology not to come with a price.
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Is there a way to access the “previous row” value in a SELECT statement?
...d to order by some column for this to be meaningful. Something like this:
select t1.value - t2.value from table t1, table t2
where t1.primaryKey = t2.primaryKey - 1
If you know how to order things but not how to get the previous value given the current one (EG, you want to order alphabetically) ...