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SQL to find the number of distinct values in a column
I can select all the distinct values in a column in the following ways:
11 Answers
11
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How to auto-indent code in the Atom editor?
...auto-indent your code in the Atom editor? In other editors you can usually select some code and auto-indent it.
11 Answers...
DropDownList in MVC 4 with Razor
...
@{
List<SelectListItem> listItems= new List<SelectListItem>();
listItems.Add(new SelectListItem
{
Text = "Exemplo1",
Value = "Exemplo1"
});
listItems.Add(new SelectListItem
{...
Can we have multiple “WITH AS” in single sql - Oracle SQL
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You can do this as:
WITH abc AS( select
FROM ...)
, XYZ AS(select
From abc ....) /*This one uses "abc" multiple times*/
Select
From XYZ.... /*using abc, XYZ multiple times*/
...
postgresql list and order tables by size
...
select table_name, pg_relation_size(quote_ident(table_name))
from information_schema.tables
where table_schema = 'public'
order by 2
This shows you the size of all tables in the schema public if you have multiple schemas, y...
Long vs Integer, long vs int, what to use and when?
...//docs.oracle.com/javase/tutorial/java/nutsandbolts/datatypes.html
byte, char .. 1B .. 8b
short int .. 2B .. 16b
int .. .. .. .. 4B .. 32b
long int .. 8B .. 64b
C .. just mess: https://en.wikipedia.org/wiki/C_data_types
short .. .. 16b
int .. .. .. 16b ... wtf?!?!
long .. .. 32b
long long .. ...
PostgreSQL function for last inserted ID
...e:
INSERT INTO persons (lastname,firstname) VALUES ('Smith', 'John');
SELECT currval('persons_id_seq');
The name of the sequence must be known, it's really arbitrary; in this example we assume that the table persons has an id column created with the SERIAL pseudo-type. To avoid relying on thi...
PostgreSQL - fetch the row which has the Max value for a column
...sted index lookup into lives - on my machine
-- the latter query plan was selected given my memory settings and
-- histogram
SELECT
l1.*
FROM
lives AS l1
INNER JOIN (
SELECT
usr_id,
MAX(time_stamp) AS time_stamp_max
FROM
lives
GROUP BY
usr_id
) AS l2
...
Highlight the difference between two strings in PHP
... Amazing! I mean the online demo with example code. Perfect char-level differences. Just WoW! :O Thank You!
– Filip OvertoneSinger Rydlo
Sep 22 '16 at 12:38
2
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Allow user to select camera or gallery for image
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How to launch a single Intent to select images from either the Gallery or the Camera, or any application registered to browse the filesystem.
Rather than creating a Dialog with a list of Intent options, it is much better to use Intent.createChooser in order...