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How to implement a unique index on two columns in rails
...st can remove the indexes who were just for one column or if I have to use all three indexes:
1 Answer
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Socket File “/var/pgsql_socket/.s.PGSQL.5432” Missing In Mountain Lion (OS X Server)
...ing the same problem with PostgreSQL that I did last year when I first installed Lion Server.
20 Answers
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How to get the last element of a slice?
...eft it outside consciously. It was non-obvious and prone to errors. Go overall is circumspect about 'too much meaning'; it also doesn't feature method/operator overloading, default values for function params, etc. which IMHO goes in a similar philosophical vein. See this discussion and others: group...
How to set a stroke-width:1 on only certain sides of SVG shapes?
...apes for each stroke or other visual style that you want to vary.
Specifically for this case, instead of using a <rect> or <polygon> element you can create a <path> or <polyline> that only covers three sides of the rectangle:
<!-- Move to 50,50 then draw a line to 150,50...
Adjusting Eclipse console size
...d, I would strongly recommend setting a high limit rather than no limit at all. If you forget to clean your console, you can run Eclipse out of heap space, IIRC.
– Matt Ball
Apr 8 '10 at 14:27
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How to use CSS to surround a number with a circle?
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The current latest version of Internet Explorer, 9, actually supports border-radius. ...and div isn't a great choice for this. :)
– reisio
Apr 25 '12 at 3:15
9
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Can't start hostednetwork
...ected the command line should bring it back.
– Tony Wall
May 17 '15 at 20:52
18
What if dont see ...
Limiting number of displayed results when using ngRepeat
...lays phones. I’m on step 5 and I thought as an experiment I’d try to allow users to specify how many they’d like to be shown. The view looks like this:
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Insert Update stored proc on SQL Server
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Your assumption is right, this is the optimal way to do it and it's called upsert/merge.
Importance of UPSERT - from sqlservercentral.com:
For every update in the case mentioned above we are removing one
additional read from the table if we
use the UPSERT instead of EXISTS.
Unfortu...
Why does PostgreSQL perform sequential scan on indexed column?
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If the SELECT returns more than approximately 5-10% of all rows in the table, a sequential scan is much faster than an index scan.
This is because an index scan requires several IO operations for each row (look up the row in the index, then retrieve the row from the heap). Whe...