大约有 43,000 项符合查询结果（耗时：0.0779秒） [XML]
Find all records which have a count of an association greater than zero
... Well that is Rails for you. If you can provide an sql answer (and explain why this isn't efficient), that may be a lot more helpful.
– jvnill
May 7 '19 at 23:17
...
Fetch first element which matches criteria
...row the NPE. To prevent that from happening, use orElse() instead of get() and provide a fallback object (like orElse(new Station("dummy", -1)), or store the result of findFirst() in a variable and check it with isEmpty() before calling get()
– ifloop
Jan 24 '1...
How to convert IEnumerable to ObservableCollection?
...myIEnumerable);
This will make a shallow copy of the current IEnumerable and turn it in to a ObservableCollection.
share
|
improve this answer
|
follow
|
...
How to globally replace a forward slash in a JavaScript string?
... be done with "string".replace('/', 'ForwardSlash', 'g') but that is non-standard argument that works only in Firefox afaik.
– Seldaek
Dec 30 '10 at 22:46
1
...
How to select only 1 row from oracle sql?
...l also work if you order by ROWID, as long as you never delete any records and always care about the last inserted/modified one.
– vapcguy
Oct 7 '16 at 21:27
...
Gets byte array from a ByteBuffer in java
...hat you want is to retrieve the bytes that are remaining (between position and limit), then what you have will work. You could also just do:
ByteBuffer bb =..
byte[] b = new byte[bb.remaining()];
bb.get(b);
which is equivalent as per the ByteBuffer javadocs.
...
How to add reference to a method parameter in javadoc?
...;/code>
* argument is the index of the first character of the subarray and
* the <code>count</code> argument specifies the length of the
* subarray. The contents of the subarray are copied; subsequent
* modification of the character array does not affect the newly
* created strin...
For files in directory, only echo filename (no path)
.../}"
done
The above uses Parameter Expansion which is native to the shell and does not require a call to an external binary such as basename
However, might I suggest just using find
find /home/user -type f -printf "%f\n"
...
XSLT getting last element
... +1. Nice one, I had forgotten you could use ( ) in that way (and was way off on the use of an indexer).
– AnthonyWJones
Sep 22 '09 at 10:35
1
...
How to define two fields “unique” as couple
...ax_length=50)
class Meta:
unique_together = ('field1', 'field2',)
And in your case:
class Volume(models.Model):
id = models.AutoField(primary_key=True)
journal_id = models.ForeignKey(Journals, db_column='jid', null=True, verbose_name = "Journal")
volume_number = models.CharField('Vol...