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Computed / calculated / virtual / derived columns in PostgreSQL
...y as column?
The expression (looking like a column) is not included in a SELECT * FROM tbl, though. You always have to list it explicitly.
Can also be supported with a matching expression index - provided the function is IMMUTABLE. Like:
CREATE FUNCTION col(tbl) ... AS ... -- your computed expr...
How to change or add theme to Android Studio?
...
File->Settings->Editor->Colors & Fonts-> In scheme name select Darcula and apply to see a awesome dark background theme editor
Android Studio 3.1.2
File->Settings->Editor->Color Scheme-> In scheme name select Darcula and apply to see a awesome dark background theme e...
How to migrate/convert from SVN to Mercurial (hg) on windows
...made
much simpler: Start the TortoiseHG
Workbench from the Start menu. Select
File --> Settings. Select Extensions
from the list. Check the 'convert'
checkbox and click OK. That's it! No
need to try to generate the config
file anymore and search it in the file
system. – bgever M...
Multiple “order by” in LINQ
...ow in _db.Movies
orderby row.Category, row.Name
select row;
[EDIT to address comment] To control the sort order, use the keywords ascending (which is the default and therefore not particularly useful) or descending, like so:
var movies = from row in _db.Movies
...
How do I select a random value from an enumeration?
Given an arbitrary enumeration in C#, how do I select a random value?
9 Answers
9
...
String.Join method that ignores empty strings?
... simpler, since you can do it in SQL directly:
PostgreSQL & MySQL:
SELECT
concat_ws(' / '
, NULLIF(searchTerm1, '')
, NULLIF(searchTerm2, '')
, NULLIF(searchTerm3, '')
, NULLIF(searchTerm4, '')
) AS RPT_SearchTerms;
And even with the glorious MS-SQ...
What GRANT USAGE ON SCHEMA exactly do?
...a schema doesn't grant rights on the tables within.
If you have rights to SELECT from a table, but not the right to see it in the schema that contains it then you can't access the table.
The rights tests are done in order:
Do you have `USAGE` on the schema?
No: Reject access.
Yes: Do...
Remove duplicate rows in MySQL
...ate temporary table tmpTable (id int);
insert into tmpTable
(id)
select id
from YourTable yt
where exists
(
select *
from YourTabe yt2
where yt2.title = yt.title
and yt2.company = yt.company
and yt2.site_id = yt.si...
How do you count the lines of code in a Visual Studio solution?
...solution's directory:
PS C:\Path> (gci -include *.cs,*.xaml -recurse | select-string .).Count
8396
PS C:\Path>
That will count the non-blank lines in all the solution's .cs and .xaml files. For a larger project, I just used a different extension list:
PS C:\Other> (gci -include *.cs,*....
EOL conversion in notepad ++
...That functionality is already built into Notepad++. From the "Edit" menu, select "EOL Conversion" -> "UNIX/OSX Format".
screenshot of the option for even quicker finding (or different language versions)
You can also set the default EOL in notepad++ via "Settings" -> "Preferences" -> "New...