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MySQL: Fastest way to count number of rows
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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...
How to use DISTINCT and ORDER BY in same SELECT statement?
..., and use a GROUP BY to make the DISTINCT work.
Try something like this:
SELECT DISTINCT Category, MAX(CreationDate)
FROM MonitoringJob
GROUP BY Category
ORDER BY MAX(CreationDate) DESC, Category
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Select tableview row programmatically
How do I programmatically select a UITableView row so that
7 Answers
7
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Vim search and replace selected text
Let's say we have a text, and I enter visual mode and select some text. How do I quickly do a search for the highlighted text and replace it with something else?
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How to get Time from DateTime format in SQL?
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SQL Server 2008:
SELECT cast(AttDate as time) [time]
FROM yourtable
Earlier versions:
SELECT convert(char(5), AttDate, 108) [time]
FROM yourtable
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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...
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 ...
Find rows with multiple duplicate fields with Active Record, Rails & Postgres
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Tested & Working Version
User.select(:first,:email).group(:first,:email).having("count(*) > 1")
Also, this is a little unrelated but handy. If you want to see how times each combination was found, put .size at the end:
User.select(:first,:email).gro...
Grouped LIMIT in PostgreSQL: show the first N rows for each group?
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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...
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.
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