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Why does my application spend 24% of its life doing a null check?
... other. With the GC heap compacting algorithm otherwise having an unpredictable affect on that. Best to not let me guess at this, measure so you know a fact.
– Hans Passant
May 15 '13 at 11:21
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Selecting data frame rows based on partial string match in a column
...rent approach. I don't know if that's a reference to the %like% from "data.table", but if it is, you can definitely use it as follows.
Note that the object does not have to be a data.table (but also remember that subsetting approaches for data.frames and data.tables are not identical):
library(dat...
How can I select multiple columns from a subquery (in SQL Server) that should have one record (selec
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select t1.*, sq.*
from table1 t1,
(select a,b,c from table2 ...) sq
where ...
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How does virtual inheritance solve the “diamond” (multiple inheritance) ambiguity?
... be only 1 instance of the base A class not 2.
Your type D would have 2 vtable pointers (you can see them in the first diagram), one for B and one for C who virtually inherit A. D's object size is increased because it stores 2 pointers now; however there is only one A now.
So B::A and C::A are...
java.net.ConnectException: Connection refused
...t also helped me, the test connection was succesfull but couldn't show any tables data.
– Damien Christophe
Aug 13 '19 at 7:52
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Remove non-utf8 characters from string
... @Alliswell If I'm not mistaken <0x1a>, although not printable character, is a perfectly valid UTF-8 sequence. You might have issues with non-printable characters? Check this: stackoverflow.com/questions/1176904/…
– Frosty Z
Mar 12 '19 at 8:...
SQL Server Profiler - How to filter trace to only display events from one database?
...lumn and find out the correct values to enter by querying the sysdatabases table in the master database
– Jim Birchall
Nov 10 '08 at 8:39
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MongoDB Show all contents from all collections
...of your database.
db.stats()
step 5: listing out all the collections(tables).
show collections
step 6:print the data from a particular collection.
db.'collection_name'.find().pretty()
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Find object by id in an array of JavaScript objects
...ore efficient, this is still a linear search, so if you want to use a hash table, see Aaron Digulla's answer (beware of impl. details).
– tne
Mar 12 '14 at 11:41
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Why does the order in which libraries are linked sometimes cause errors in GCC?
...linker will not link to libraries that are not actually needed by the executable (and it detects this from left to right). My recent archlinux distribution doesn't use this flag by default, so it didn't give an error for not following the correct order.
It is not correct to omit the dependency of b...