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Are Java static calls more or less expensive than non-static calls?
... If I trained a parrot to say "premature opimisation is the root of all evil" I'd get 1000 votes from people who know as much about performance as the parrot.
– rghome
Jan 28 '19 at 14:54
...
SQL how to increase or decrease one for a int column in one command
...eral ways to do this. Since you did not specify a database, I will assume MySQL.
INSERT INTO table SET x=1, y=2 ON DUPLICATE KEY UPDATE x=x+1, y=y+2
REPLACE INTO table SET x=1, y=2
They both can handle your question. However, the first syntax allows for more flexibility to update the record ra...
How do SQL EXISTS statements work?
... FROM SUPPLIERS JOIN ORDERS ... on SQL Server, haven't tested on Oracle or MySQL lately.
– OMG Ponies
May 1 '11 at 16:40
...
How to expand/collapse a diff sections in Vimdiff?
...
gvim -d main.sql backup.sql &
I find that annoyingly one file has MySQL keywords in lowercase the other uppercase showing differences on practically every other line
:set diffopt+=icase
this updates the screen dynamically & you can just as easily switch it off again
...
How to use the same C++ code for Android and iOS?
...nsider these things as boilerplate.
One significant thing and usually the root of a lot of problems is the name of the method; it needs to follow the pattern "Java_package_class_method". Currently, Android studio has excellent support for it so it can generate this boilerplate automatically and sho...
Parallel.ForEach vs Task.Factory.StartNew
.... I made a research calling the following method:
public static double SumRootN(int root)
{
double result = 0;
for (int i = 1; i < 10000000; i++)
{
result += Math.Exp(Math.Log(i) / root);
}
return result;
}
Execution of this method takes about 0.5se...
了解 Boost Filesystem Library - C/C++ - 清泛网 - 专注C/C++及内核技术
... 的字符串的副本，其格式符合 path 语法规则。
std::string root_directory( )：在提供了路径的情况下，此 API 将返回根目录，否则将返回空字符串。例如，如果路径包含/tmp/var1，则此例程将返回 /，即 UNIX 文件系统的根。不过，如果路...
How to delete images from a private docker registry?
...arbage-collect /etc/docker/registry/config.yml
Here is my config.yml
root@c695814325f4:/etc# cat /etc/docker/registry/config.yml
version: 0.1
log:
fields:
service: registry
storage:
cache:
blobdescriptor: inmemory
filesystem:
rootdirectory: /var/lib/registry
del...
Create SQL script that create database and tables
...
Anyway to do this is standard SQL for mysql for example?
– Benjamin Goodacre
Oct 21 '19 at 11:56
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Float vs Decimal in ActiveRecord
...In Rails 4.1.0, I have faced problem with saving latitude and longitude to MySql database. It can't save large fraction number with float data type. And I change the data type to decimal and working for me.
def change
change_column :cities, :latitude, :decimal, :precision => 15, :scale =...