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Alter MySQL table to add comments on columns
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Script for all fields on database:
SELECT
table_name,
column_name,
CONCAT('ALTER TABLE `',
TABLE_SCHEMA,
'`.`',
table_name,
'` CHANGE `',
column_name,
'` `',
column_name,
'` ',
column_typ...
Can you use hash navigation without affecting history?
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Unless you use :target selectors ... then history functions are useless, as that part of the spec (css interaction with history ops) seems to be not defined currently, and style does not get recomputed on history replace by most/all browsers.
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How to check status of PostgreSQL server Mac OS X
...using psql to run a simple query and checking the exit code, e.g. psql -c 'SELECT 1', or use pg_isready to check the connection status.
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if checkbox is checked, do this
...heckbox').click(function(){
var chk = $(this);
$('p').toggleClass('selected', chk.attr('checked'));
})
in this way your code it's cleaner because you don't have to specify all css properties (let's say you want to add a border, a text style or other...) but you just switch a class
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How to flatten tree via LINQ?
...IEnumerable<MyNode> Flatten(IEnumerable<MyNode> e) =>
e.SelectMany(c => Flatten(c.Elements)).Concat(new[] { e });
You can then filter by group using Where(...).
To earn some "points for style", convert Flatten to an extension function in a static class.
public static IEnume...
ERROR 2006 (HY000): MySQL server has gone away
...L/MariaDB server.
Double check the value was set properly by:
mysql -sve "SELECT @@max_allowed_packet" # or:
mysql -sve "SHOW VARIABLES LIKE 'max_allowed_packet'"
You got a timeout from the TCP/IP connection on the client side.
Solution: Increase wait_timeout variable.
You tried to run a query a...
When to Redis? When to MongoDB? [closed]
...e, writing stupid sql statements... not just one but freaking everywhere. "select this, select that". But in particular you remember the irritating WHERE clause. Where lastname equals "thornton" and movie equals "bad santa." Urgh. You think, "why don’t those dbas just do their job and give me som...
Polymorphism in C++
...egorise them in various ways:
When is the polymorphic type-specific code selected?
Run time means the compiler must generate code for all the types the program might handle while running, and at run-time the correct code is selected (virtual dispatch)
Compile time means the choice of type-specif...
Xcode 4 - slow performance
...sure Xcode isn't open. Now find your project file. Right-click on it, and select Show Package Contents.
Next, delete project.xcworkspace.
Open Xcode and enjoy faster performance!
Thanks to:
http://meachware.blogspot.com/2011/06/speed-up-xcode-4.html
Edit: I've gotten several comments a...
Format number to 2 decimal places
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Show as decimal
Select ifnull(format(100.00, 1, 'en_US'), 0)
100.0
Show as Percentage
Select concat(ifnull(format(100.00, 0, 'en_US'), 0), '%')
100%
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