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Select text on input focus
I have a text input. When the input receives focus I want to select the text inside of the input.
10 Answers
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Can someone explain collection_select to me in clear, simple terms?
I am going through the Rails API docs for collection_select and they are god-awful.
2 Answers
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SQL - using alias in Group By
... following order:
FROM clause
WHERE clause
GROUP BY clause
HAVING clause
SELECT clause
ORDER BY clause
For most relational database systems, this order explains which names (columns or aliases) are valid because they must have been introduced in a previous step.
So in Oracle and SQL Server, you...
What's faster, SELECT DISTINCT or GROUP BY in MySQL?
...'t, then use DISTINCT.
GROUP BY in MySQL sorts results. You can even do:
SELECT u.profession FROM users u GROUP BY u.profession DESC
and get your professions sorted in DESC order.
DISTINCT creates a temporary table and uses it for storing duplicates. GROUP BY does the same, but sortes the disti...
MySQL case insensitive select
Can anyone tell me if a MySQL SELECT query is case sensitive or case insensitive by default? And if not, what query would I have to send so that I can do something like:
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How can I list ALL grants a user received?
...ust direct table grants (e.g., grants via roles, system privileges such as select any table, etc.), here are some additional queries:
System privileges for a user:
SELECT PRIVILEGE
FROM sys.dba_sys_privs
WHERE grantee = <theUser>
UNION
SELECT PRIVILEGE
FROM dba_role_privs rp JOIN role_...
Difference between left join and right join in SQL Server [duplicate]
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Select * from Table1 left join Table2 ...
and
Select * from Table2 right join Table1 ...
are indeed completely interchangeable. Try however Table2 left join Table1 (or its identical pair, Table1 right join Table2) to see...
jquery select change event get selected option
I bound an event on the change event of my select elements with this:
9 Answers
9
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Set the selected index of a Dropdown using jQuery
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First of all - that selector is pretty slow. It will scan every DOM element looking for the ids. It will be less of a performance hit if you can assign a class to the element.
$(".myselect")
To answer your question though, there are a few w...
Function to Calculate Median in SQL Server
... in all cases. It also requires SQL 2012 or later.
DECLARE @c BIGINT = (SELECT COUNT(*) FROM dbo.EvenRows);
SELECT AVG(1.0 * val)
FROM (
SELECT val FROM dbo.EvenRows
ORDER BY val
OFFSET (@c - 1) / 2 ROWS
FETCH NEXT 1 + (1 - @c % 2) ROWS ONLY
) AS x;
Of course, just because o...