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How to count occurrences of a column value efficiently in SQL?
...
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...
How do I run Visual Studio as an administrator by default?
...indows 8, 8.1 and 10
In Windows 8, you have to right-click devenv.exe and select "Troubleshoot compatibility".
Select "Troubleshoot program"
Check "The program requires additional permissions"
click "Next", click "Test the program..."
Wait for the program to launch
Click "Next"
Select "Yes, save ...
T-SQL get SELECTed value of stored procedure
...UTPUT parameter and a result set
ALSO, watch out if you use the pattern: SELECT @Variable=column FROM table ...
if there are multiple rows returned from the query, your @Variable will only contain the value from the last row returned by the query.
RETURN VALUE
since your query returns an int fie...
MySQL JOIN the most recent row only?
...
You may want to try the following:
SELECT CONCAT(title, ' ', forename, ' ', surname) AS name
FROM customer c
JOIN (
SELECT MAX(id) max_id, customer_id
FROM customer_data
GROUP BY customer_id
...
jQuery - setting the selected value of a select control via its text description
I have a select control, and in a javascript variable I have a text string.
21 Answers
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jquery get all form elements: input, textarea & select
Is there an easy way (without listing them all separately) in jquery to select all form elements and only form elements.
12...
How to show all privileges from a user in oracle?
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You can try these below views.
SELECT * FROM USER_SYS_PRIVS;
SELECT * FROM USER_TAB_PRIVS;
SELECT * FROM USER_ROLE_PRIVS;
DBAs and other power users can find the privileges granted to other users with the DBA_ versions of these same views. They are cov...
How do I get the current time zone of MySQL?
...bal and client-specific time zones can be retrieved like this:
mysql> SELECT @@global.time_zone, @@session.time_zone;
Edit The above returns SYSTEM if MySQL is set to slave to the system's timezone, which is less than helpful. Since you're using PHP, if the answer from MySQL is SYSTEM, you ca...
How to get a number of random elements from an array?
...- Math.random());
// Get sub-array of first n elements after shuffled
let selected = shuffled.slice(0, n);
DEMO:
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Generating random strings with T-SQL
...st varchar(8000)
declare @step bigint = rand(@seed) * 2147483647;
select @alpha = 'qwertyuiopasdfghjklzxcvbnm'
, @digit = '1234567890'
, @specials = '_@# '
select @first = @alpha + '_@';
set @seed = (rand((@seed+@step)%2147483647)*2147483647);
select @length =...