大约有 9,780 项符合查询结果（耗时：0.0165秒） [XML]
Is the NOLOCK (Sql Server hint) bad practice?
...
With NOLOCK hint, the transaction isolation level for the SELECT statement is READ UNCOMMITTED. This means that the query may see dirty and inconsistent data.
This is not a good idea to apply as a rule. Even if this dirty read behavior is OK for your mission critical web based app...
Default filter in Django admin
...lookup, title in self.lookup_choices:
yield {
'selected': self.value() == lookup,
'query_string': cl.get_query_string({
self.parameter_name: lookup,
}, []),
'display': title,
}
def querys...
Restore LogCat window within Android Studio
...e bottom). Use the "gear" at the extreme top right of the log cat section; select floating mode. Confusingly it then "appears to be docked" still ... just grab the bar and move it around. (If you're used to Mac, it's a little confusing.) (Android Studio is awesome on Mac eh??)
...
visual c++: #include files from other projects in the same solution
...n.
To access the project configuration:
Right-click on the project, and select Properties.
Select Configuration Properties->C/C++->General.
Set the path under Additional Include Directories.
How to include
To include the header file, simply write the following in your code:
#include "fi...
How do I remove javascript validation from my eclipse project?
...validation all together is too drastic. Fortunately with Eclipse, you can selectively remove some JavaScript sources from validation.
Right-click your project.
Navigate to: Properties → JavaScript → Include Path
Select Source tab. (It looks identical to Java Build Path Source tab.)
Expand Jav...
UPDATE multiple tables in MySQL using LEFT JOIN
...= t1.id
SET t1.col1 = newvalue
WHERE t2.id IS NULL
Note that for a SELECT it would be more efficient to use NOT IN / NOT EXISTS syntax:
SELECT t1.*
FROM t1
WHERE t1.id NOT IN
(
SELECT id
FROM t2
)
See the article in my blog for performance details...
Explicit vs implicit SQL joins
...e joined and how they are joined. Try compare larger SQL queries where you selecting from 8 different tables and you have lots of filtering in the where. By using join syntax you separate out the parts where the tables are joined, to the part where you are filtering the rows.
...
Android Studio: Add jar as library?
.... Click the + sign above the panel second from the left -> Java
4.4. Select your local jar and add it to the project.
You may need to run the above ./gradlew command one more time
share
|
imp...
Why can't I reference System.ComponentModel.DataAnnotations?
...odel.DataAnnotations assembly (Solution explorer -> Add reference -> Select .Net tab -> select System.ComponentModel.DataAnnotations from the list)
share
|
improve this answer
|
...
ERROR: permission denied for sequence cities_id_seq using Postgres
...
Since PostgreSQL 8.2 you have to use:
GRANT USAGE, SELECT ON SEQUENCE cities_id_seq TO www;
GRANT USAGE - For sequences, this privilege allows the use of the currval and nextval functions.
Also as pointed out by @epic_fil in the comments you can grant permissions to all th...