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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 do I (or can I) SELECT DISTINCT on multiple columns?
...
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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How to do a JUnit assert on a message in a logger
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@s.d If you cast the Logger to org.apache.logging.log4j.core.Logger (the implementation class for the interface) you'll get access to setAppender()/removeAppender() again.
– David Moles
Dec 10 '19 a...
How to convert SecureString to System.String?
...rtainly use the unsafe keyword and a char*, just call bstr.ToPointer() and cast.
– Ben Voigt
Jun 21 '16 at 16:23
@BenV...
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*/
...
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...
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...
Passing an array to a query using a WHERE clause
...y external input is sanitized.
$ids = join("','",$galleries);
$sql = "SELECT * FROM galleries WHERE id IN ('$ids')";
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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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