大约有 6,000 项符合查询结果（耗时：0.0337秒） [XML]
What is this operator in MySQL?
...d and therefore supported on other databases, unlike <=>, which is MySQL-specific.
You can think of them as specialisations of MySQL's <=>:
'a' IS NULL ==> 'a' <=> NULL
'a' IS NOT NULL ==> NOT('a' <=> NULL)
Based on this, your particular query (fragment) can be con...
MongoDB and “joins” [duplicate]
...in since the relationship will only be evaluated when needed. A join (in a SQL database) on the other hand will resolve relationships and return them as if they were a single table (you "join two tables into one").
You can read more about DBRef here:
http://docs.mongodb.org/manual/applications/data...
Effect of NOLOCK hint in SELECT statements
... about it by a colleague and my initial research made me question myself. SQLServer 2005 documentation says that with NOLOCK is the default locking scheme for all select statements! I'd guess then that my hints would be redundant in ...
– Bob Probst
Oct 16 '0...
phpmyadmin logs out after 1440 secs
In my local development Ubuntu box I use MySQL and phpmyadmin to work with the database.
24 Answers
...
Throw an error in a MySQL trigger
...
As of MySQL 5.5, you can use the SIGNAL syntax to throw an exception:
signal sqlstate '45000' set message_text = 'My Error Message';
State 45000 is a generic state representing "unhandled user-defined exception".
Here is a more...
How can I put a database under git (version control)?
...
PostGreSQL database files are binary files, feel free to put them in your git repository, you just won't be able to do any diffs on them, and any changes will most likely change the whole database and thus you now have to send the f...
How to change the default charset of a MySQL table?
There is a MySQL table which has this definition taken from SQLYog Enterprise :
5 Answers
...
PostgreSQL: How to make “case-insensitive” query
Is there any way to write case-insensitive queries in PostgreSQL, E.g. I want that following 3 queries return same result.
...
Should I commit or rollback a read transaction?
...mization points for your app. If you're really curious, you can find the mySQL transaction handling code at bazaar.launchpad.net/~mysql/mysql-server/mysql-6.0/annotate/…
– Mark Brackett
May 21 '10 at 15:05
...
Getting “Lock wait timeout exceeded; try restarting transaction” even though I'm not using a transac
I'm running the following MySQL UPDATE statement:
17 Answers
17
...