英文:
How to perform SQL batch updates to update one property in Entity Framework Core 6 C#
问题
以下是您要的翻译：
我有以下代码，用于使用Entity Framework在Azure SQL表中执行更新操作
public class DatabaseRepo
{
private readonly UserContext _context;
public DatabaseRepo(UserContext userContext)
{
_context = userContext;
}
public async Task BatchUpdateUsersAsync(List<User> users)
{
foreach (var user in users)
{
var entity = await _context.Users
.FirstOrDefaultAsync(item => item.Id == user.Id);
entity.StartDate = user.StartDate;
await _context.SaveChangesAsync();
}
}
}
我只想更新所有这些用户的“StartDate”值。是否有更好的批量更新方法？
我正在使用EF Core 6
我尝试了这个：
public async Task BatchUpdateUsersAsync(List<User> users)
{
foreach (var user in users)
{
var entry = _context.Set<User>().Add(user);
entry.State = EntityState.Modified;
}
await _context.SaveChangesAsync();
}
但这会引发关于其他属性不能为空的错误。
英文:
I have the following code to perform an update in Azure SQL table using Entity Framework
public class DatabaseRepo
{
private readonly UserContext _context;
public DatabaseRepo(UserContext userContext)
{
_context = userContext;
}
public async Task BatchUpdateUsersAsync(List<User> users)
{
foreach (var user in users)
{
var entity = await _context.Users
.FirstOrDefaultAsync(item => item.Id == user.Id);
entity.StartDate = user.StartDate;
await _context.SaveChangesAsync();
}
}
}
All I want to do update StartDate value of all these users. Is there a better way to do batch update?
I'm using EF Core 6
I tried this:
public async Task BatchUpdateUsersAsync(List<User> users)
{
foreach (var user in users)
{
var entry = _context.Set<User>().Add(user);
entry.State = EntityState.Modified;
}
await _context.SaveChangesAsync();
}
but this throws an error about some other property can't be null.
答案1
得分: 3
EF Core 7引入了新的批量更新功能，包括更新和删除。
来自Microsoft的信息：ExecuteUpdate和ExecuteDelete
您可以使用以下代码：
var dateTime = DateTime.Now;
_context.Users
.Where(p => p.IsActive || p.Username == "DoNotUpdateMe")
.ExecuteUpdate(p => p.SetProperty(x => x.StartDate, x => dateTime));
_context.SaveChanges();
英文:
EF Core 7 introduces new bulk update features, including update and delete.
Info from Microsoft: ExecuteUpdate and ExecuteDelete
You can use the following:
var dateTime = DateTime.Now;
_context.Users
.Where(p => p.IsActive || p.Username == "DoNotUpdateMe")
.ExecuteUpdate(p => p.SetProperty(x => x.StartDate, x => dateTime));
_context.SaveChanges();
答案2
得分: 0
`Attach` 更新仅需要的列，这些列的 `IsModified` 值为 true，代码如下：
public async Task BatchUpdateUsersAsync(List<User> users)
{
foreach (var user in users)
{
_context.Set<User>().Attach(user);
_OSTContext.Entry(user).Property(x => x.StartDate).IsModified = true; // 仅更新 Startdate 列
}
await _context.SaveChangesAsync();
}
这将适用于任何 Entity Framework 版本
英文:
Attach Updates only Required column's those are IsModified =true code will be as follows
public async Task BatchUpdateUsersAsync(List<User> users)
{
foreach (var user in users)
{
_context.Set<User>().Attach(user);
_OSTContext.Entry(user).Property(x => x.StartDate).IsModified = true; //updates only Startdate Column
}
await _context.SaveChangesAsync();
}
This will be use any Entity Frame work version
答案3
得分: -2
你可以使用Select方法进行批量更新，文档中的性能数值如下所示。
public class DatabaseRepo
{
private readonly UserContext _context;
public DatabaseRepo(UserContext userContext)
{
_context = userContext;
}
public async Task BatchUpdateUsersAsync(List<User> users)
{
var entities = users.Select(async (user) => await _context.Users.FirstOrDefaultAsync(item => item.Id == user.Id));
entities.ExecuteUpdate(p => p.SetProperty(u => u.StartDate, u => DateTime.Now));
await _context.SaveChangesAsync();
}
}
英文:
You can use the Select method for batch updates, the performance values in the documentation are shared below.
public class DatabaseRepo
{
private readonly UserContext _context;
public DatabaseRepo(UserContext userContext)
{
_context = userContext;
}
public async Task BatchUpdateUsersAsync(List<User> users)
{
var entities = users.Select(async (user) => await _context.Users.FirstOrDefaultAsync(item => item.Id == user.Id));
entities.ExecuteUpdate(p => p.SetProperty(u => u.StartDate, u => DateTime.Now));
await _context.SaveChangesAsync();
}
}
通过集体智慧和协作来改善编程学习和解决问题的方式。致力于成为全球开发者共同参与的知识库，让每个人都能够通过互相帮助和分享经验来进步。
评论