大约有 40,000 项符合查询结果（耗时：0.0338秒） [XML]
quick random row selection in Postgres
...u want to use a higher LIMIT... I need to get 3 items so I need to use the ORDER BY RANDOM() syntax.
– Alexis Wilke
Nov 24 '12 at 1:29
1
...
How to perform OR condition in django queryset?
...t just works. As you'd expect, the | binary operator returns a QuerySet so order_by(), .distinct(), and other queryset filters can be tacked on to the end.
combined_queryset = User.objects.filter(income__gte=5000) | User.objects.filter(income__isnull=True)
ordered_queryset = combined_queryset.order...
How to sort an ArrayList in Java [duplicate]
...s and adding each fruit in the list. I want to sort this list based on the order of fruit name.
3 Answers
...
How to sort ArrayList in decreasing order?
How to sort an ArrayList<Long> in Java in decreasing order?
14 Answers
14
...
Get: TypeError: 'dict_values' object does not support indexing when using python 3.2.3 [duplicate]
...ersion of this implementation is UNSAFE. You should not rely on dictionary order. For example doing d=dict(**d) may change the iteration order of keys.
– xaviersjs
Oct 2 '19 at 0:08
...
How do I use a PriorityQueue?
...d pass in a comparator which compares in the appropriate way for your sort order. If you give an example of how you want to sort, we can provide some sample code to implement the comparator if you're not sure. (It's pretty straightforward though.)
As has been said elsewhere: offer and add are just d...
Breadth First Vs Depth First
... / / \
D E F
A depth first traversal would visit the nodes in this order
A, B, D, C, E, F
Notice that you go all the way down one leg before moving on.
A breadth first traversal would visit the node in this order
A, B, C, D, E, F
Here we work all the way across each level before going...
SqlException from Entity Framework - New transaction is not allowed because there are other threads
...ds, you can write your query like this:
foreach (var client in clientList.OrderBy(c => c.Id).QueryInChunksOf(100))
{
// do stuff
context.SaveChanges();
}
The queryable object you call this method on must be ordered. This is because Entity Framework only supports IQueryable<T>.Sk...
boost多索引容器multi_index_container实战 - C/C++ - 清泛网 - 专注C/C++及内核技术
...
#include "boost/multi_index/member.hpp"
#include "boost/multi_index/ordered_index.hpp"
using boost::multi_index_container;
using namespace boost::multi_index;
struct stu_num{}; // 索引-学号
struct stu_name{}; // 索引-姓名
struct stu_age{}; // 索引-年龄 ...
C++ Structure Initialization
...
@user1043000 well, for one, in this case the order in which you put your members is of upmost importance. If you add a field in the middle of your structure, you will have to go back to this code and look for the exact spot in which to insert your new initialization, wh...