问在rails中通过一次调用保存多个对象ENRails 6引入了一种新方法insert_all，它在一条SQL INSERT语句中插入多条记录到数据库中。import java.lang.reflect.Method; class MethodInvokeTest { public static void main(String[] args) throws Exception { String str = "hello"; Method m = str.getClass().getMetho...
153 changes: 153 additions & 0 deletions 153 activerecord/lib/active_record/insert_all.rb @@ -0,0 +1,153 @@ # frozen_string_literal: true module ActiveRecord class InsertAll attr_reader :model, :connection, :inserts, :on_duplicate, :returning, :unique_by def initialize(model, inserts, ...
class ItemsController < ApplicationController def update item_ids = params[:item_ids] Item.where(id: item_ids).update_all(selected: true) redirect_to items_path end end 在上述示例中,我们使用update_all方法来将选中的记录的selected字段更新为true。你可以根据实际需求进行修改。 这样,当用户...
add_indexremove_indexadd_timestampsnewcreatefindfind_byfind_eachfind_or_create_byfind_by_sqlallfirstlasttakeselectwherenotandororderdistinctnonelimitoffsetjoinsleft_outer_joinsincludesgrouphavingcountcount_by_sqlpluckpicksaveupdateupdate_alltouchinsert_alldeletedelete_alldelete_bydestroydestroy_alldestroy_by...
At some point, we all need to insert multiple records in one go and have found many workarounds when doing so. Well, Rails 6 comes with a new method out of the box—insert_all, similar toupdate_all. It won’t fire any callbacks and will execute a single SQL query. There is an ...
(count=10000)Post.insert_all!((1..count).map{{title:SecureRandom.alphanumeric}})endend Output: Post Exists? (0.1ms) SELECT 1 AS one FROM "posts" LIMIT ? [["LIMIT", 1]] Post Load (8.6ms) SELECT "posts".* FROM "posts" Post Exists? (0.7ms) SELECT 1 AS one FROM "posts" LIMIT...
在实际项目中一般不用delete或者delete_all删除数据,因为这样删除的数据是不可恢复的。 #删除第一个name为"可爱的猫宁"的对象 irb(main):019:0> Account.where(name:"可爱的猫宁").first.delete => #<Account id: 1, name: "可爱的猫宁", email: "12345@", password: nil, role: nil, status: nil,...
# Bulk create BrewCommandRuns for each Device.# Since there are no callbacks or validations on# BrewCommandRun, we can safely use insert_all!## rubocop:disable Rails/SkipsModelValidationsBrewCommandRun.insert_all!(new_brew_command_runs)# rubocop:enable Rails/SkipsModelValidations ...
我们在代码中看不到与 INSERT、UPDATE、DELETE 和 SELECT * 查询有关的 SQL 语句,而每个 Model 类都会使用这类查询。这类代码是在后台生成的。但是,旧模式的一个共同特征就是需要复杂的 SQL 语句来检索或汇总数据。另外,Oracle 数据库还提供其他 RDBMS 中没有的强大功能。例如,它可以使用单个层次查询生成数据的...
page.insert_html :bottom, 'expenses', :partial => 'expense' page.visual_effect :highlight, "expense-#{@expense.id}" page.replace_html 'total-amount', number_to_currency(@project.total_expenses) page.form.reset 'expense-form' end