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What are the performance characteristics of sqlite with very large database files? [closed]
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So I did some tests with sqlite for very large files, and came to some conclusions (at least for my specific application).
The tests involve a single sqlite file with either a single table, or multiple tables. Each table had about 8 columns, almost all integers, and 4 indices.
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LIKE vs CONTAINS on SQL Server
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The second (assuming you means CONTAINS, and actually put it in a valid query) should be faster, because it can use some form of index (in this case, a full text index). Of course, this form of query is only available if the column is in a full text index. If it isn...
Can a CSV file have a comment?
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The CSV "standard" (such as it is) does not dictate how comments should be handled, no, it's up to the application to establish a convention and stick with it.
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Is it possible to remove inline styles with jQuery?
...ery plugin is applying an inline style ( display:block ). I'm feeling lazy and want to override it with display:none .
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How to overwrite the previous print to stdout in python?
...w that Python 2 is EOL, a Python 3 answer makes more sense. For Python 3.5 and earlier:
for x in range(10):
print('{}\r'.format(x), end="")
print()
In Python 3.6 and later, f-strings read better:
for x in range(10):
print(f'{x}\r', end="")
print()
Of course, as Tim Seguine points out in th...
Increase heap size in Java
...ou ask for 5g on a 32 bit system java will complain about an invalid value and quit.
As others have posted, use the cmd-line flags - e.g.
java -Xmx6g myprogram
You can get a full list (or a nearly full list, anyway) by typing java -X.
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jQuery set checkbox checked
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Taking all of the proposed answers and applying them to my situation - trying to check or uncheck a checkbox based on a retrieved value of true (should check the box) or false (should not check the box) - I tried all of the above and found that using .prop("ch...
No mapping found for field in order to sort on in ElasticSearch
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Hi, I have the same problem and I don't understand how this works... The attributes missing and ignore_unmapped should work together right ? If for example I set missing to "_last" and ignore_unmapped to "false", I still have the problem but I want the ...
How to pass arguments and redirect stdin from a file to program run in gdb?
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Pass the arguments to the run command from within gdb.
$ gdb ./a.out
(gdb) r < t
Starting program: /dir/a.out < t
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Converting an array of objects to ActiveRecord::Relation
... ActiveRecord::Relation since a Relation is just a builder for a SQL query and its methods do not operate on actual data.
However, if what you want is a relation then:
for ActiveRecord 3.x, don’t call all and instead call scoped, which will give back a Relation which represents the same records...