大约有 3,620 项符合查询结果（耗时：0.0101秒） [XML]
Difference between attr_accessor and attr_accessible
... "users" that contains three columns "firstname", "lastname" and "role" :
SQL instructions :
CREATE TABLE users (
firstname string,
lastname string
role string
);
I assumed that you set the option config.active_record.whitelist_attributes = true in your config/environment/production.rb to ...
windows service vs scheduled task
...ication. OR .. they are continuously-running heavyweight applications like SQL Server, BizTalk, RPC Connections, IIS (even though IIS technically offloads work to other processes).
Personally, I favour scheduled tasks over Window Services for repititive maintenance tasks and applications such as fi...
Entity framework linq query Include() multiple children entities
... .FirstOrDefault(co => co.companyID == companyID);
The Sql generated in both instances is still by no means intuitive, but seems performant enough. I've put a small example on GitHub here
EF Core
EF Core has a new extension method, .ThenInclude(), although the syntax is slightl...
Two single-column indexes vs one two-column index in MySQL?
...
"MySQL can use multiple-column indexes for queries that test all the columns in the index, or queries that test just the first column, the first two columns, the first three columns, and so on. If you specify the columns in the ...
What is scope/named_scope in rails?
...call
Zombie.rotting.fresh.recent.limit(3)
It translates to the below in SQL,
select "zombies.*" from "zombies" where "zombies"."rotting" = 't' and (age<20) order by create_at desc limit 3
Example above is based on rails 4 syntax
...
How to obtain the start time and end time of a day?
...er compliant with JDBC 4.2 or later. No need for strings, no need for java.sql.* classes. Hibernate 5 & JPA 2.2 support java.time.
Where to obtain the java.time classes?
Java SE 8, Java SE 9, Java SE 10, Java SE 11, and later - Part of the standard Java API with a bundled implementation.
Java...
What framework for MVVM should I use? [closed]
...validation
viewmodel base classes: relaycommand, closeableviewmodel…
SQL server data access layer
Basic MVVM framework
• Author: Lester Lobo
• Silverlight support: no
• Documentation: sample application available with the library
• Hosting: CodePlex
• Lic...
How to return a file using Web API?
...le(long id)
{
HttpResponseMessage result = null;
try
{
SQL.File file = db.Files.Where(b => b.ID == id).SingleOrDefault();
if (file == null)
{
result = Request.CreateResponse(HttpStatusCode.Gone);
}
else
{
// send...
Calling shell functions with xargs
...c 'echo_var "$@"' _ {}
$(date)
This is comparable to using parameterized SQL queries to avoid injection.
I'm using date in a command substitution or in escaped quotes here instead of the rm command used in Sasha's comment since it's non-destructive.
...
Converting between datetime, Timestamp and datetime64
...nk this is the best answer I've ever seen. Coming from Excel, VBA, SAS, or SQL, Python seems weird because there's not just "one way" to work with dates/times. As with many things in Python or R, it seems one must choose a favourite method/module/class and stick with it.
– Sean...