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Is there any difference between GROUP BY and DISTINCT
...CT and distinct by UNION cause an oracle error, but GROUP BY worked; I was selecting only 1 column from a view and not using any aggregation; I'm still baffled why it required it, but it does confirm there is some difference in the execution. As others point out, it also lets you GROUP BY columns no...
Is it possible to center text in select box?
...you could style the dropdown:
https://www.filamentgroup.com/lab/jquery-ui-selectmenu-an-aria-accessible-plugin-for-styling-a-html-select.html
This plugin hides the select element, and creates span elements etc on the fly to display a custom drop down list style. I'm quite confident you'd be able t...
How to detect when cancel is clicked on file input?
...s not exposed to the browser." This is not true if the dialog is closed by selecting a file.
– Trevor
Dec 1 '16 at 22:24
...
How do you connect to multiple MySQL databases on a single webpage?
...d);
$dbh2 = mysql_connect($hostname, $username, $password, true);
mysql_select_db('database1', $dbh1);
mysql_select_db('database2', $dbh2);
Then to query database 1 pass the first link identifier:
mysql_query('select * from tablename', $dbh1);
and for database 2 pass the second:
mysql_query...
jQuery removing '-' character from string
I have a string "-123445". Is it possible to remove the '-' character from the string?
3 Answers
...
What is the syntax for an inner join in LINQ to SQL?
...ke:
from t1 in db.Table1
join t2 in db.Table2 on t1.field equals t2.field
select new { t1.field2, t2.field3}
It would be nice to have sensible names and fields for your tables for a better example. :)
Update
I think for your query this might be more appropriate:
var dealercontacts = from conta...
How does one reorder columns in a data frame?
...
You can also use the subset function:
data <- subset(data, select=c(3,2,1))
You should better use the [] operator as in the other answers, but it may be useful to know that you can do a subset and a column reorder operation in a single command.
Update:
You can also use the select...
Get top n records for each group of grouped results
...ould need to specify the group number and add queries for each group:
(
select *
from mytable
where `group` = 1
order by age desc
LIMIT 2
)
UNION ALL
(
select *
from mytable
where `group` = 2
order by age desc
LIMIT 2
)
There are a variety of ways to do this, see this articl...
Any way to select without causing locking in MySQL?
...s/22-mysql-with-nolock.aspx
in MS SQL Server you would do the following:
SELECT * FROM TABLE_NAME WITH (nolock)
and the MYSQL equivalent is
SET SESSION TRANSACTION ISOLATION LEVEL READ UNCOMMITTED ;
SELECT * FROM TABLE_NAME ;
SET SESSION TRANSACTION ISOLATION LEVEL REPEATABLE READ ;
EDIT
Mic...
TypeError: 'str' does not support the buffer interface
...k for the rest of the world. Measure the length of a word with a non-ASCII character?
py2>> len('¡no') #length of string=3, length of UTF-8 byte array=4, since with variable len encoding the non-ASCII chars = 2-6 bytes
4 #always gives bytes.len not str.len
All ...