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How can I tell when a MySQL table was last updated?
...e information_schema database to tell you when another table was updated:
SELECT UPDATE_TIME
FROM information_schema.tables
WHERE TABLE_SCHEMA = 'dbname'
AND TABLE_NAME = 'tabname'
This does of course mean opening a connection to the database.
An alternative option would be to "touch" a ...
How many GCC optimization levels are there?
...?
integral_argument also thinly wraps atoi and rejects the argument if any character is not a digit. So negative values fail gracefully.
Back to opts.c:default_options_optimization, we see the line:
if ((unsigned int) opts->x_optimize > 255)
opts->x_optimize = 255;
so that the optimizati...
How to make the first option of selected with jQuery
How do I make the first option of selected with jQuery?
27 Answers
27
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Update multiple rows in same query using PostgreSQL
...;
-- populate table with dummy rows
insert into results_dummy
(id, status)
select unnest(array[1,2,3,4,5]::int[]) as id, unnest(array['a','b','c','d','e']::text[]) as status;
select * from results_dummy;
-- THE update of multiple rows with/by different values
update results_dummy as rd
set stat...
What is a good Hash Function?
... that differ only in the last 4 bytes can collide easily. If you have a 30 character string, that differ in the last 4 bytes, after 28 bytes have been processes, the hashes differ only in the last 2 bytes. That means you are GUARANTEED a collision for one of the remaining two-byte values. (Yeah, it'...
Is there a MySQL option/feature to track history of changes to records?
...i AFTER INSERT ON MyDB.data FOR EACH ROW
INSERT INTO MyDB.data_history SELECT 'insert', NULL, NOW(), d.*
FROM MyDB.data AS d WHERE d.primary_key_column = NEW.primary_key_column;
CREATE TRIGGER MyDB.data__au AFTER UPDATE ON MyDB.data FOR EACH ROW
INSERT INTO MyDB.data_history SELECT 'up...
The definitive guide to form-based website authentication [closed]
...
A cryptographic hash should not be used for password storage because user-selected passwords are not strong enough (i.e. do not usually contain enough entropy) and a password guessing attack could be completed in a relatively short time by an attacker with access to the hashes. This is why KDFs are...
HTML5: number input type that takes only integers?
...f chrome. It does not allow letters to be typed, but it does allow special characters to be inserted.
– Malavos
Feb 21 '15 at 21:39
3
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Why does Git treat this text file as a binary file?
... inspected the file's contents it has seen stuff that isn't in basic ascii characters. Being UTF16 I expect that it will have 'funny' characters so it thinks it's binary.
There are ways of telling git if you have internationalisation (i18n) or extended character formats for the file. I'm not suffic...
Is there a function to deselect all text using JavaScript?
Is there a function in javascript to just deselect all selected text? I figure it's got to be a simple global function like document.body.deselectAll(); or something.
...