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MySQL - force not to use cache for testing speed of query
...ry cache at server startup, set the query_cache_size system variable to 0. By disabling the query cache code, there is no noticeable overhead. If you build MySQL from source, query cache capabilities can be excluded from the server entirely by invoking configure with the --without-query-cache option...
Flask-SQLAlchemy how to delete all rows in a single table
....filter(Model.id==123).delete()
db.session.commit()
Delete Single Record by Object
record_obj = db.session.query(Model).filter(Model.id==123).first()
db.session.delete(record_obj)
db.session.commit()
https://flask-sqlalchemy.palletsprojects.com/en/2.x/queries/#deleting-records
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What is the Objective-C equivalent for “toString()”, for use with NSLog?
...on also reserved? Although I think DebugDescription is supposed to be used by a debugger like LLDB.
– MaddTheSane
Oct 23 '14 at 1:09
add a comment
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Why no generics in Go?
...e C#'s System.Object (or Java's Object per se) is essentially what I meant by "C's void pointers" (ignoring the part that you can't do pointer arithmetic in those languages). Those are where the static type information gets lost. A cast will not help much because you will get a runtime error.
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Replace all spaces in a string with '+' [duplicate]
...i he wants to replace spaces, not "white spaces." In this context I assume by spaces he means only the space character, not just any old whitespace like /s would match. Particularly because he is doing this in JavaScript, and replacing the space character (but not other whitespace) with the + charac...
What is the most useful script you've written for everyday life? [closed]
... example:
/a/very/deeply/nested/path/somewhere> up 4
/a/very>
NB by gmatt:
Working off the great work above, it can be extended to a back function by placing the following into your bashrc:
function up( )
{
LIMIT=$1
P=$PWD
for ((i=1; i <= LIMIT; i++))
do
P=$P/..
done
cd $P
export ...
List all the modules that are part of a python package?
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what is this importer returned by pkgutil.iter_modules? Can I use it to import a module instead of using this seemly "hackish" __import__(modname, fromlist="dummy") ?
– MestreLion
Nov 5 '13 at 22:41
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Reshaping data.frame from wide to long format
...tations that give the same result:
# you can also define the id-variables by column number
melt(wide, id.vars = 1:2)
# as an alternative you can also specify the measure-variables
# all other variables will then be used as id-variables
melt(wide, measure.vars = 3:7)
melt(wide, measure.vars = as.ch...
A Better Django Admin ManyToMany Field Widget
...ry read only_fields = ('users',) . But Its shown in single line separated by comma. I want to shown in line break ...
– Varnan K
Dec 31 '14 at 8:11
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Conditional HTML Attributes using Razor MVC3
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You can force Razor to evaluate code by putting parens around it. id="track_@(track.ID)"
– Erik Porter
Jan 27 '12 at 18:42
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