大约有 40,000 项符合查询结果（耗时：0.0377秒） [XML]
Why is using the rails default_scope often recommend against?
... of default_scope is when you want something to be sorted: default_scope { order(:name) }.
– user2985898
Aug 25 '16 at 9:33
...
What is a deadlock?
...cks that can be aquired at the same time and they are grabbed in different order.
Ways to avoid having deadlocks are:
avoid having locks (if possible),
avoid having more than one lock
always take the locks in the same order.
...
How to create the perfect OOP application [closed]
...ll comes together to print this receipt:
------------------ THIS IS YOUR ORDER ------------------
(001) Domain Driven Design ----- $69.99
(001) Growing Object Oriented Software ----- $49.99
(001) House M.D. Season 1 ----- $29.99
(001) House M...
Rank items in an array using Python/NumPy, without sorting array twice
...
Use argsort twice, first to obtain the order of the array, then to obtain ranking:
array = numpy.array([4,2,7,1])
order = array.argsort()
ranks = order.argsort()
When dealing with 2D (or higher dimensional) arrays, be sure to pass an axis argument to argsort to...
Difference between partition key, composite key and clustering key in Cassandra?
...tition key columns, then you can add optionally each clustering key in the order they're set.
so the valid queries are (excluding secondary indexes)
col1 and col2
col1 and col2 and col10
col1 and col2 and col10 and col 4
Invalid:
col1 and col2 and col4
anything that does not contain both col1...
How to get values from IGrouping
...
Isn't that the same as a normal "orderBy"? List<smth> newList = list .OrderBy(x => x.id).ToList();
– MorgoZ
Apr 22 '16 at 11:42
...
SQL Server CTE and recursion example
...loyees
WHERE EmployeeID = cteReports.MgrID) AS Manager
FROM cteReports
ORDER BY EmpLevel, MgrID
The simplest example of a recursive CTE I can think of to illustrate its operation is;
;WITH Numbers AS
(
SELECT n = 1
UNION ALL
SELECT n + 1
FROM Numbers
WHERE n+1 <= 10
)
S...
Select SQL Server database size
... , RowNum = ROW_NUMBER() OVER (PARTITION BY s.database_name, s.[type] ORDER BY s.backup_finish_date DESC)
FROM msdb.dbo.backupset s
WHERE s.[type] IN ('D', 'L')
) f
WHERE f.RowNum = 1
GROUP BY f.database_name
) bu ON d.name = bu.database_name
ORDER BY t.total_size DE...
Entity Framework Code First - two Foreign Keys from same table
...
public int MatchId { get; set; }
[ForeignKey("HomeTeam"), Column(Order = 0)]
public int? HomeTeamId { get; set; }
[ForeignKey("GuestTeam"), Column(Order = 1)]
public int? GuestTeamId { get; set; }
public float HomePoints { get; set; }
public float GuestPoints { get; se...
Disable sorting for a particular column in jQuery DataTables
...les example - HTML5 data-* attributes - table options
So you can use data-orderable="false" on the th of the column you don't want to be sortable. For example, the second column "Avatar" in the table below will not be sortable:
<table id="example" class="display" width="100%" data-page-length="...