大约有 44,000 项符合查询结果(耗时:0.0501秒) [XML]

https://stackoverflow.com/ques... 

How to get the number of days of difference between two dates on mysql?

...lues are used in the calculation In your case, you'd use : mysql> select datediff('2010-04-15', '2010-04-12'); +--------------------------------------+ | datediff('2010-04-15', '2010-04-12') | +--------------------------------------+ | 3 | +--------------...
https://stackoverflow.com/ques... 

TSQL - Cast string to integer or return default value

...ing DECLARE @Test TABLE(Value nvarchar(50)) -- Result INSERT INTO @Test SELECT '1234' -- 1234 INSERT INTO @Test SELECT '1,234' -- 1234 INSERT INTO @Test SELECT '1234.0' -- 1234 INSERT INTO @Test SELECT '-1234' -- -1234 INSERT INTO @Test SELECT '$1234' ...
https://stackoverflow.com/ques... 

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...
https://stackoverflow.com/ques... 

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'...
https://stackoverflow.com/ques... 

How to remove selected commit log entries from a Git repository while keeping their changes?

I would like to remove selected commit log entries from a linear commit tree, so that the entries do not show in the commit log. ...
https://stackoverflow.com/ques... 

How to make ng-repeat filter out duplicate results

... unique filter) and use it directly in the ng-options (or ng-repeat). <select ng-model="orderProp" ng-options="place.category for place in places | unique:'category'"> <option value="0">Default</option> // unique options from the categories </select> ...
https://stackoverflow.com/ques... 

In SQL, what's the difference between count(column) and count(*)?

...a values(null,1) insert #bla values(1,null) insert #bla values(null,null) select count(*),count(id),count(id2) from #bla results 7 3 2 share | improve this answer | fo...
https://stackoverflow.com/ques... 

What are the uses for Cross Join?

...ly, like size and color information for a particular article of clothing: select size, color from sizes CROSS JOIN colors Maybe you want a table that contains a row for every minute in the day, and you want to use it to verify that a procedure has executed each minute, so you might c...
https://stackoverflow.com/ques... 

How to set auto increment primary key in PostgreSQL?

...able(moobars,foobars) values('worldwide interblag','2012-05-02') Step 3, select * from your table: el@voyager$ psql -U pgadmin -d kurz_prod -c "select * from epictable" Step 4, interpret the output: mytable_key | moobars | foobars -------------+-----------------------+------...
https://stackoverflow.com/ques... 

PostgreSQL: How to pass parameters from command line?

...3="'2010-11-12'" and then refer to the variables in sql as :v1, :v2 etc select * from table_1 where id = :v1; Please pay attention on how we pass string/date value using two quotes " '...' " share | ...