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What's the Point of Multiple Redis Databases?
...e instances lets you take advantage of multiple cores. If you use database selection you will have to refactor when upgrading. Monitoring and managing multiple instances is not difficult nor painful.
Indeed, you would get far better metrics on each db by segregation based on instance. Each instanc...
How do write IF ELSE statement in a MySQL query
...
You probably want to use a CASE expression.
They look like this:
SELECT col1, col2, (case when (action = 2 and state = 0)
THEN
1
ELSE
0
END)
as state from tbl1;
share
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...
Intelli J IDEA takes forever to update indices
...ks perfectly. Thanks for the solution friends.
Just:
Open IntelliJ IDEA
Select the File menu
Select the Invalidate Caches / Restart... menu.
Once selected you get a pop-up with a bunch of options.
Select Invalidate and Restart
and before doing that make sure you saved all your changes else it mig...
Trim trailing spaces in Xcode
...
You can create a script and bind it to a keyboard shortcut:
Select Scripts Menu > Edit User Scripts...
Press the + button and select New Shell Script
Give it a name like "Strip Trailing Spaces", and give it a shortcut like ⌃⇧R.
Set Input to "Selection" and Output to "Replace Se...
intellij - spring is not being recognized (Unmapped Spring configuration)
...alog (either by clicking the warning or through file=>project structure
select the modules item in the left hand list
go through and right click on the modules with missing files and select Add=>Spring
in the new tab click the + button
you should now see a list of the xml files. Check the box...
Export from sqlite to csv using shell script
...qlite3
You have a separate call to sqlite3 for each line; by the time your select runs, your .out out.csv has been forgotten.
Try:
#!/bin/bash
./bin/sqlite3 ./sys/xserve_sqlite.db <<!
.headers on
.mode csv
.output out.csv
select * from eS1100_sensor_results;
!
instead.
sh/bash methods
You can...
Paste multiple times
...
Clever. 'p' to paste, 'gv' to re-select what was originally selected. 'y' to copy it again.
– Amjith
Aug 23 '11 at 21:17
...
Generate random numbers using C++11 random library
...;
}
};
thread_local backoff_time_t backoff_time;
int main(int argc, char** argv) {
double x1 = backoff_time.rand();
double x2 = backoff_time.rand();
double x3 = backoff_time.rand();
double x4 = backoff_time.rand();
return 0;
}
~
...
Why does PostgreSQL perform sequential scan on indexed column?
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If the SELECT returns more than approximately 5-10% of all rows in the table, a sequential scan is much faster than an index scan.
This is because an index scan requires several IO operations for each row (look up the row in the ...
How to use if-else option in JSTL
...prefix="c" uri="http://www.springframework.org/tags/form"%>
and
<c:select>
<option value="RCV"
${records[0].getDirection() == 'RCV' ? 'selected="true"' : ''}>
<spring:message code="dropdown.Incoming" text="dropdown.Incoming" />
...