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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...
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...
How to drop all tables in a SQL Server database?
...VARCHAR(500) DECLARE @Cursor CURSOR
SET @Cursor = CURSOR FAST_FORWARD FOR
SELECT DISTINCT sql = 'ALTER TABLE [' + tc2.TABLE_SCHEMA + '].[' + tc2.TABLE_NAME + '] DROP [' + rc1.CONSTRAINT_NAME + '];'
FROM INFORMATION_SCHEMA.REFERENTIAL_CONSTRAINTS rc1
LEFT JOIN INFORMATION_SCHEMA.TABLE_CONSTRAINTS t...
How to solve the error LNK2019: unresolved external symbol - function?
...me so I thought I might share my solution, as simple as it was:
Check the Character Set of both projects in Configuration Properties -> General -> Character Set
My UnitTest project was using the default Character Set Multi-Byte while my libs where in Unicode.
My function was using a TCHAR as...
Convert special characters to HTML in Javascript
Does any one know how to convert special characters to HTML in Javascript ?
26 Answers
...
Removing rounded corners from a element in Chrome/Webkit
...sheet for Chrome gives a border-radius of 5px to all the corners of a <select> element. I've tried getting rid of this by applying a radius of 0px through my external stylesheet, as well inline on the element itself; I've tried both border-radius:0px and -webkit-border-radius:0px; and I...
Simple way to calculate median with MySQL
...
In MariaDB / MySQL:
SELECT AVG(dd.val) as median_val
FROM (
SELECT d.val, @rownum:=@rownum+1 as `row_number`, @total_rows:=@rownum
FROM data d, (SELECT @rownum:=0) r
WHERE d.val is NOT NULL
-- put some where clause here
ORDER BY d.val
) ...
How to insert a newline in front of a pattern?
...adability - the only caveat is that you then need to double all literal \ chars.
– mklement0
Nov 30 '15 at 3:59
...
Sublime Text 2 multiple line edit
...t and edit all lines at once.
It's also called "Split into Lines" in the "Selection" menu.
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Drawing an image from a data URL to a canvas
...
in javascript , using jquery for canvas id selection :
var Canvas2 = $("#canvas2")[0];
var Context2 = Canvas2.getContext("2d");
var image = new Image();
image.src = "images/eye.jpg";
Context2.drawImage(image, 0, 0);
html5:
<canv...