在 rails 中的一次调用中保存多个对象 [英] Saving multiple objects in a single call in rails

问题描述

我在 rails 中有一个方法可以做这样的事情:

I have a method in rails that is doing something like this:

a = Foo.new("bar")
a.save

b = Foo.new("baz")
b.save

...
x = Foo.new("123", :parent_id => a.id)
x.save

...
z = Foo.new("zxy", :parent_id => b.id)
z.save

问题是，我添加的实体越多，所需的时间就越长.我怀疑这是因为它必须为每条记录访问数据库.因为它们是嵌套的，所以我知道我不能在父母被拯救之前拯救孩子，但我想一次拯救所有的父母，然后是所有的孩子.做这样的事情会很好:

The problem is this takes longer and longer the more entities I add. I suspect this is because it has to hit the database for every record. Since they are nested, I know I can't save the children before the parents are saved, but I would like to save all of the parents at once, and then all of the children. It would be nice to do something like:

a = Foo.new("bar")
b = Foo.new("baz")
...
saveall(a,b,...)

x = Foo.new("123", :parent_id => a.id)
...
z = Foo.new("zxy", :parent_id => b.id)
saveall(x,...,z)

只需两次数据库命中即可完成所有操作.有没有一种简单的方法可以在 Rails 中做到这一点，还是我一次只能做一个?

That would do it all in only two database hits. Is there an easy way to do this in rails, or am I stuck doing it one at a time?

推荐答案

insert_all (Rails 6+)

Rails 6 引入了一种新方法 insert_all，它在单个 SQL INSERT 语句中将多条记录插入到数据库中.

insert_all (Rails 6+)

Rails 6 introduced a new method insert_all, which inserts multiple records into the database in a single SQL INSERT statement.

此外，此方法不会实例化任何模型，并且不会调用 Active Record 回调或验证.

所以，

Foo.insert_all([
  { first_name: 'Jamie' },
  { first_name: 'Jeremy' }
])

它明显比

Foo.create([
  { first_name: 'Jamie' },
  { first_name: 'Jeremy' }
])

如果您只想插入新记录.

if all you want to do is to insert new records.

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