大约有 42,000 项符合查询结果（耗时：0.0338秒） [XML]
Django filter queryset __in for *every* item in list
...(self):
return self.name
In [2]: t1 = Tag.objects.create(name='holiday')
In [3]: t2 = Tag.objects.create(name='summer')
In [4]: p = Photo.objects.create()
In [5]: p.tags.add(t1)
In [6]: p.tags.add(t2)
In [7]: p.tags.all()
Out[7]: [<Tag: holiday>, <Tag: summer>]
Using chained f...
Add new item count to icon on button - Android
... TextView as an XML <shape> drawable, with which you can create a solid or gradient circle with a border. An XML drawable will scale to fit the view as it resizes with more or less text.
res/drawable/badge_circle.xml:
<shape xmlns:android="http://schemas.android.com/apk/res/android"
an...
Delete sql rows where IDs do not have a match from another table
...
Using LEFT JOIN/IS NULL:
DELETE b FROM BLOB b
LEFT JOIN FILES f ON f.id = b.fileid
WHERE f.id IS NULL
Using NOT EXISTS:
DELETE FROM BLOB
WHERE NOT EXISTS(SELECT NULL
FROM FILES f
WHERE f.id = fileid)
Using NOT IN:
DELETE FROM BLOB
WHERE fi...
SQL JOIN - WHERE clause vs. ON clause
...
They are not the same thing.
Consider these queries:
SELECT *
FROM Orders
LEFT JOIN OrderLines ON OrderLines.OrderID=Orders.ID
WHERE Orders.ID = 12345
and
SELECT *
FROM Orders
LEFT JOIN OrderLines ON OrderLines.OrderID=Orders.ID
AND Orders.ID = 1234...
How to get ID of the last updated row in MySQL?
How do I get the ID of the last updated row in MySQL using PHP?
12 Answers
12
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JPA - Returning an auto generated id after persist()
...EclipseLink) and Spring. Say I have a simple entity with an auto-generated ID:
7 Answers
...
How to add an auto-incrementing primary key to an existing table, in PostgreSQL?
...le named test1, to which you want to add an auto-incrementing, primary-key id (surrogate) column. The following command should be sufficient in recent versions of PostgreSQL:
ALTER TABLE test1 ADD COLUMN id SERIAL PRIMARY KEY;
Older Versions of PostgreSQL
In old versions of PostgreSQL (prior ...
In Flux architecture, how do you manage Store lifecycle?
...1. Flux assumes this situation is an eventuality in a large application. Ideally this situation would not need to happen, and developers should strive to avoid this complexity, if possible. But the singleton Dispatcher is ready to handle it when the time comes.
Stores are singletons as well. Th...
How to develop a soft keyboard for Android? [closed]
I would like to play around with some ideas and develop a soft keyboard for Android to replace the default one.
4 Answers
...
Disable a Maven plugin defined in a parent POM
...or me when disabling Findbugs in a child POM:
<plugin>
<groupId>org.codehaus.mojo</groupId>
<artifactId>findbugs-maven-plugin</artifactId>
<executions>
<execution>
<id>ID_AS_IN_PARENT</id> <!-- id is necessary ...