大约有 40,000 项符合查询结果(耗时:0.0397秒) [XML]
How to store arrays in MySQL?
...the key.". An array does too much. It has multiple facts and it stores the order (which is not related to the relation itself). And the performance is poor (see above).
Imagine that you have a person table and you have a table with phone calls by people. Now you could make each person row have a li...
Sorting an IList in C#
...d an Engine property, I believe you could sort as follows:
from c in list
orderby c.Engine
select c;
Edit: You do need to be quick to get answers in here. As I presented a slightly different syntax to the other answers, I will leave my answer - however, the other answers presented are equally val...
How to do a SOAP Web Service call from Java class?
... layer.)
About the second approach (create your custom SOAP client):
In order to implement the second approach, you'll have to:
Make the call:
Use the SAAJ (SOAP with Attachments API for Java) framework (see below, it's shipped with Java SE 1.6 or above) to make the calls; or
You can also do ...
Write to UTF-8 file in Python
...u've given me a byte string!"
Try writing the Unicode string for the byte order mark (i.e. Unicode U+FEFF) directly, so that the file just encodes that as UTF-8:
import codecs
file = codecs.open("lol", "w", "utf-8")
file.write(u'\ufeff')
file.close()
(That seems to give the right answer - a fil...
Print array elements on separate lines in Bash?
...ame -a "${alpha[@]}"
Using shuf; note that results might not come out in order:
shuf -e "${alpha[@]}"
share
|
improve this answer
|
follow
|
...
SQL left join vs multiple tables on FROM line?
... Employee.DepartmentID
Note that the last one there is an inner join, in order to fulfill the criteria that you only want departments with people.
Ok, so what happens now. Well, the problem is, it depends on the database engine, the query optimizer, indexes, and table statistics. Let me explain.
...
What is the difference between Non-Repeatable Read and Phantom Read?
... will allow dirty reads, which in some cases is an acceptable trade off in order to achieve higher concurrency or is necessary due to an edge case, such as troubleshooting an in progress transaction from another connection. It is good that the idea of a dirty read doesn't pass the "smell test" for y...
SQLAlchemy: print the actual query
...compile(dialect=postgresql.dialect()))
When given an ORM Query object, in order to get at the compile() method we only need access the .statement accessor first:
statement = query.statement
print(statement.compile(someengine))
with regards to the original stipulation that bound parameters are to b...
Command line: piping find results to rm
... intend to use with
-delete, you should explicitly specify -depth in order to avoid
later surprises. Because -delete implies -depth, you cannot
usefully use -prune and -delete together.
P.S. Note that piping directly to rm isn't an option, because rm doesn't expect filenames on stan...
How does Django's Meta class work?
...t of django
Model metadata is “anything that’s not a field”, such as ordering options (ordering), database table name (db_table), or human-readable singular and plural names (verbose_name and verbose_name_plural). None are required, and adding class Meta to a model is completely optional.
http...