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Hibernate, @SequenceGenerator and allocationSize
We all know the default behaviour of Hibernate when using @SequenceGenerator - it increases real database sequence by one , multiple this value by 50 (default allocationSize value) - and then uses this value as entity ID.
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What does mysql error 1025 (HY000): Error on rename of './foo' (errorno: 150) mean?
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You usually get this error if your tables use the InnoDB engine. In that case you would have to drop the foreign key, and then do the alter table and drop the column.
But the tricky part is that you can't drop the foreign key using...
Error 1022 - Can't write; duplicate key in table
...ou can not have the same foreign key names in the database tables.
Check all your tables and all your foreign keys and avoid having two foreign keys with the same exact name.
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How do I compare two strings in Perl?
...rldoc perlop for more information.
( I'm simplifying this a little bit as all but cmp return a value that is both an empty string, and a numerically zero value instead of 0, and a value that is both the string '1' and the numeric value 1. These are the same values you will always get from boolean o...
Best practice for creating millions of small temporary objects
What are the "best practices" for creating (and releasing) millions of small objects?
13 Answers
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What is the best way to paginate results in SQL Server
...E OrderDate >= '1980-01-01'
...which may seem inefficient, but is actually pretty performant, assuming all indexes etc. are properly set up.
Next, to get actual results back in a paged fashion, the following query would be most efficient:
SELECT *
FROM ( SELECT ROW_NUMBER() OVER ( ORDE...
how to return index of a sorted list? [duplicate]
...ray([2,3,1,4,5])
>>> vals
array([2, 3, 1, 4, 5])
>>> sort_index = numpy.argsort(vals)
>>> sort_index
array([2, 0, 1, 3, 4])
If not available, taken from this question, this is the fastest method:
>>> vals = [2,3,1,4,5]
>>> sorted(range(len(vals)), key=...
How to get Scala List from Java List?
...now built into the language using:
import scala.collection.JavaConversions._
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lst.toList.foreach{ node => .... }
works. asScala did not work
In 2.12.x use import scala.collection.JavaConverters._
In 2.13.x use import scala.jdk.CollectionConverters._
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HTML minification? [closed]
...s are very high that the cost/benefit for this effort is negligible, especially if you were planning to manually use online tools to deal with each page.
Use YSlow or Page Speed to determine what you really need to do to optimize your pages. My guess is that reducing bytes of HTML will not be yo...
How to ignore deprecation warnings in Python
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This doesn't work for me at all, still seeing deprecationwarnings.
– user1244215
Oct 22 '13 at 0:43
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