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Adding 'serial' to existing column in Postgres
...int, b text);
CREATE TABLE bar (a serial, b text);
INSERT INTO foo (a, b) SELECT i, 'foo ' || i::text FROM generate_series(1, 5) i;
INSERT INTO bar (b) SELECT 'bar ' || i::text FROM generate_series(1, 5) i;
-- blocks of commands to turn foo into bar
CREATE SEQUENCE foo_a_seq;
ALTER TABLE foo ALTER...
How to launch Safari and open URL from iOS app
... You can directly use URL instead of NSURL so you can save the cast.
– marsbear
Jul 21 '17 at 9:04
1
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How to convert a string to integer in C?
... @chux thanks! Can you explain a bit more why the (unsigned char) cast could make a difference?
– Ciro Santilli 郝海东冠状病六四事件法轮功
May 30 '16 at 13:00
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How do I (or can I) SELECT DISTINCT on multiple columns?
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SELECT DISTINCT a,b,c FROM t
is roughly equivalent to:
SELECT a,b,c FROM t GROUP BY a,b,c
It's a good idea to get used to the GROUP BY syntax, as it's more powerful.
For your query, I'd do it like this:
UPDATE sale...
resizes wrong; appears to have unremovable `min-width: min-content`
I have a <select> where one of its <option> ’s text values is very long. I want the <select> to resize so it is never wider than its parent, even if it has to cut off its displayed text. max-width: 100% should do that.
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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*/
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How to count occurrences of a column value efficiently in SQL?
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This should work:
SELECT age, count(age)
FROM Students
GROUP by age
If you need the id as well you could include the above as a sub query like so:
SELECT S.id, S.age, C.cnt
FROM Students S
INNER JOIN (SELECT age, count(age) a...
Meaning of epsilon argument of assertEquals for double values
...an call assertEquals(Object, Object) instead:
// really you just need one cast because of autoboxing, but let's be clear
assertEquals((Object)Double.MIN_VALUE, (Object)defaultValue);
And, if you really want to look clever:
assertEquals(
Double.doubleToLongBits(Double.MIN_VALUE),
Double....
Populating a razor dropdownlist from a List in MVC
...leaner separation.
First create a viewmodel to store the Id the user will select along with a list of items that will appear in the DropDown.
ViewModel:
public class UserRoleViewModel
{
// Display Attribute will appear in the Html.LabelFor
[Display(Name = "User Role")]
public int Sele...
How to get equal width of input and select fields
On the form, I have one select and two input fields. These elements are vertically aligned. Unfortunately, I can't get equal width of these elements.
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