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MySQL: Fastest way to count number of rows
...s.
The solution is SQL_CALC_FOUND_ROWS. This is usually used when you are selecting rows but still need to know the total row count (for example, for paging).
When you select data rows, just append the SQL_CALC_FOUND_ROWS keyword after SELECT:
SELECT SQL_CALC_FOUND_ROWS [needed fields or *] FROM t...
MySQL: Selecting multiple fields into multiple variables in a stored procedure
Can I SELECT multiple columns into multiple variables within the same select query in MySQL?
3 Answers
...
Select tableview row programmatically
How do I programmatically select a UITableView row so that
7 Answers
7
...
How to map and remove nil values in Ruby
...blem:
N = 1_00_000
enum = 1.upto(1_000)
Benchmark.bmbm do |x|
x.report("select + map") { N.times { enum.select { |i| i.even? }.map{|i| i + 1} } }
x.report("map + compact") { N.times { enum.map { |i| i + 1 if i.even? }.compact } }
x.report("filter_map") { N.times { enum.filter_map { |i| i ...
DISTINCT for only one column
...
If you are using SQL Server 2005 or above use this:
SELECT *
FROM (
SELECT ID,
Email,
ProductName,
ProductModel,
ROW_NUMBER() OVER(PARTITION BY Email ORDER BY ...
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 get Time from DateTime format in SQL?
...
SQL Server 2008:
SELECT cast(AttDate as time) [time]
FROM yourtable
Earlier versions:
SELECT convert(char(5), AttDate, 108) [time]
FROM yourtable
share
|...
How to change Android Studio's editor font?
...TRL + mouse wheel which is really easy to use it !!!
To use this feature select File -> Settings -> Editor -> General -> select the checkbox of Change the font size (Zoom) with Ctrl + Mouse Wheel
I hope it's helpful.
...
How to delete duplicates on a MySQL table?
...n an index is going to be slow for large tables. Wouldn't it be better to SELECT MAX(ID) FROM t GROUP BY unique and then JOIN to an exact match of ID to MAX(ID)?
– ebyrob
Nov 10 '16 at 16:31
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Grouped LIMIT in PostgreSQL: show the first N rows for each group?
...
New solution (PostgreSQL 8.4)
SELECT
*
FROM (
SELECT
ROW_NUMBER() OVER (PARTITION BY section_id ORDER BY name) AS r,
t.*
FROM
xxx t) x
WHERE
x.r <= 2;
sha...