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SQL Server equivalent of MySQL's NOW()?
...nt (though if you're porting code between database vendors, that'll be the least of your worries). It's exactly the same as GetDate() under the covers (see this question for more on that).
There's no ANSI equivalent for GetUTCDate(), however, which is probably the one you should be using if your ap...
What are the main disadvantages of Java Server Faces 2.0?
...g the character yourself anywhere in client ID's, such as -.
Last but not least, a new scope was introduced, the view scope. It eliminated another major JSF 1.x disadvantage as described before. You just declare the bean @ViewScoped to enable the conversation scope without hassling all ways to reta...
Are there any O(1/n) algorithms?
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This question isn't as stupid as it might seem. At least theoretically, something such as O(1/n) is completely sensible when we take the mathematical definition of the Big O notation:
Now you can easily substitute g(x) for 1/x … it's obvious that the above definition sti...
Does every Core Data Relationship have to have an Inverse?
...In practice, I haven't had any data loss due to not having an inverse - at least that I am aware of. A quick Google suggests you should use them:
An inverse relationship doesn't just
make things more tidy, it's actually
used by Core Data to maintain data
integrity.
-- Cocoa Dev Central
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How to set the font style to bold, italic and underlined in an Android TextView?
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I checked it in 2.1. So at least it should work from 2.1 and above
– Andro Selva
Oct 14 '12 at 2:03
1
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Check if at least two out of three booleans are true
...is question: given three boolean variables, a, b, and c, return true if at least two out of the three are true.
63 Answers
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Include all existing fields and add new fields to document
... This seems to be the best current solution, as you can (at least in JS) then use the spread operator to rebuild your original object with the new custom_field attached. const newObj = { ...result.document, custom_field: result.custom_field }
– ffritz
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Least common multiple for 3 or more numbers
How do you calculate the least common multiple of multiple numbers?
31 Answers
31
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MySQL: Invalid use of group function
...!= b.sid
GROUP BY a.pid
Which I believe should return only rows where at least two rows exist with the same pid but there is are at least 2 sids. To make sure you get back only one row per pid I've applied a grouping clause.
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How to concatenate strings of a string field in a PostgreSQL 'group by' query?
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How about using Postgres built-in array functions? At least on 8.4 this works out of the box:
SELECT company_id, array_to_string(array_agg(employee), ',')
FROM mytable
GROUP BY company_id;
share
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