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How to remove leading and trailing whitespace in a MySQL field?
...d the use case before using this solution:
trim does not work while doing select query
This works
select replace(name , ' ','') from test;
While this doesn't
select trim(name) from test;
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LINQ: Select an object and change some properties without creating a new object
.... But here is the expanded LINQ expression example.
var query = someList.Select(x => { x.SomeProp = "foo"; return x; })
What this does is use an anonymous method vs and expression. This allows you to use several statements in one lambda. So you can combine the two operations of setting the ...
Jquery select all elements that have $jquery.data()
Select elements that i have previously set with jquery.data();
7 Answers
7
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Fastest Way to Find Distance Between Two Lat/Long Points
...ate a SPATIAL index on these points
Use MBRContains() to find the values:
SELECT *
FROM table
WHERE MBRContains(LineFromText(CONCAT(
'('
, @lon + 10 / ( 111.1 / cos(RADIANS(@lon)))
, ' '
, @lat + 10 / 111.1
, ','
, @lon - 10 / ( 111.1 / cos(RADI...
Ruby: Easiest Way to Filter Hash Keys?
...answer: Even though this is answer (as of the time of this comment) is the selected answer, the original version of this answer is outdated.
I'm adding an update here to help others avoid getting sidetracked by this answer like I did.
As the other answer mentions, Ruby >= 2.5 added the Hash#sli...
MySQL: Fastest way to count number of rows
...s.
The solution is SQL_CALC_FOUND_ROWS. This is usually used when you are selecting rows but still need to know the total row count (for example, for paging).
When you select data rows, just append the SQL_CALC_FOUND_ROWS keyword after SELECT:
SELECT SQL_CALC_FOUND_ROWS [needed fields or *] FROM t...
Why Android Studio says “Waiting For Debugger” if am NOT debugging?
...e. Just go to "Android device"->"Settings"->"Developer Options"->"Select app to be debugged". It will likely be pointing to your application. Just select the option and then select "None".
Note: As mentioned, even if "None" is already selected, re-selecting "None" appears to correct the pr...
Tracking CPU and Memory usage per process
...tility to save the performance data for your inspection later. To do this, select "Performance Logs and Alerts" in the left-hand panel. (It's right under the System Monitor console which provides us with the above mentioned counters. If it is not there, click "File" > "Add/remove snap-in", click ...
Find value in an array
...
Using Array#select will give you an array of elements that meet the criteria. But if you're looking for a way of getting the element out of the array that meets your criteria, Enumerable#detect would be a better way to go:
array = [1,2,...
Fluent and Query Expression — Is there any benefit(s) of one over other?
...me in fullNames
from name in fullName.Split()
orderby fullName, name
select name + " came from " + fullName;
Now compare this to the same thing in method syntax:
var query = fullNames
.SelectMany (fName => fName.Split().Select (name => new { name, fName } ))
.OrderBy (x => x.fN...