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What is PAGEIOLATCH_SH wait type in SQL Server?
... like this:
Select * from <table> where <col1> = <value> order by <PrimaryKey>
, check that you have a composite index on (col1, col_primary_key).
If you don't have one, then you'll need either a full INDEX SCAN if the PRIMARY KEY is chosen, or a SORT if an index on col1 is ...
Loop through an array of strings in Bash?
...example below it is changed to a comma
List="Item 1,Item 2,Item 3"
Backup_of_internal_field_separator=$IFS
IFS=,
for item in $List;
do
echo $item
done
IFS=$Backup_of_internal_field_separator
Output:
Item 1
Item 2
Item 3
If need to number them:
`
this is called a back tick. Put t...
Allowed characters in Linux environment variable names
...EE Std
1003.1-2001 consist solely of uppercase letters, digits, and the '_'
(underscore) from the characters
defined in Portable Character Set and
do not begin with a digit. Other
characters may be permitted by an
implementation; applications shall
tolerate the presence of such names.
...
Conditional compilation and framework targets
...rgetFrameworkVersion.Replace('v', '')) >= 2.0 ">$(DefineConstants)NET_20_OR_GREATER, </DefineConstants>
<DefineConstants Condition=" $(TargetFrameworkVersion.Replace('v', '')) >= 3.5 ">$(DefineConstants)NET_35_OR_GREATER</DefineConstants>
<DefineConstants Condition=...
Lock, mutex, semaphore… what's the difference?
...task to another. A mutex is meant to be taken and released, always in that order, by each task that uses the shared resource it protects. By contrast, tasks that use semaphores either signal or wait—not both."
– ToolmakerSteve
Feb 2 '17 at 5:14
...
What is the easiest/best/most correct way to iterate through the characters of a string in Java?
...
In Java 8 we can solve it as:
String str = "xyz";
str.chars().forEachOrdered(i -> System.out.print((char)i));
str.codePoints().forEachOrdered(i -> System.out.print((char)i));
The method chars() returns an IntStream as mentioned in doc:
Returns a stream of int zero-extending the cha...
How can we programmatically detect which iOS version is device running on? [duplicate]
...j/CJAMacros/blob/master/CJAMacros/CJAMacros.h
Like this:
#define SYSTEM_VERSION_EQUAL_TO(v) ([[[UIDevice currentDevice] systemVersion] compare:v options:NSNumericSearch] == NSOrderedSame)
#define SYSTEM_VERSION_GREATER_THAN(v) ([[[UIDevice currentDevice] systemVersi...
What does -D_XOPEN_SOURCE do/mean?
... the gcc man page, but did not find this specific option. I did find XOPEN_SOURCE , but there was little explanation of what it does.
...
rgdal package installation
...file update
Then, when you get an error such as :
configure: error: proj_api.h not found in standard or given locations.
You can use the following command to find which package you must install to get the missing file :
$ apt-file search proj_api.h
libproj-dev: /usr/include/proj_api.h
...
How to save an image locally using Python whose URL address I already know?
...wered Nov 27 '11 at 15:01
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