postgresql create trigger 文心快码BaiduComate 在PostgreSQL中,触发器(Trigger)是一种特殊类型的存储过程,它会在指定的表上对某些事件(如INSERT、UPDATE或DELETE操作)做出响应并自动执行。触发器通常用于强制复杂的业务规则、维护数据的完整性或记录数据的更改历史。 以下是创建PostgreSQL触发器的步骤,包括编写SQL语句、...
在PostgreSQL中,创建触发器的语法如下: CREATETRIGGERtrigger_name {BEFORE|AFTER|INSTEADOF} {event [OR...]} ONtable_name [FOR[EACH] {ROW| STATEMENT}] [WHEN(condition)] EXECUTEFUNCTIONfunction_name() •trigger_name:触发器的名称,必须在所属的表中是唯一的。 •BEFORE | AFTER | INSTEAD OF:指定...
PostgreSQL trigger functions are similar to regularuser-defined functions. They are invoked when a particular database event (for example INSERT, UPDATE, DELETE) occurs. Triggers do not take any argument or parameters and return a value having a typetrigger. What are Triggers in Postgres? Trigge...
删除行之前的PostgreSQL Create Trigger 假设我们有一个表users,我们希望在删除某一行之前记录一些日志信息。我们可以创建一个BEFORE DELETE触发器来实现这个功能。 示例代码 代码语言:txt 复制 -- 创建日志表 CREATE TABLE user_delete_log ( id SERIAL PRIMARY KEY, user_id INT NOT NULL, deleted_at TIMESTAMP ...
PostgreSQL 14にコミットされたCREATE OR REPLACE TRIGGERの機能を紹介。新しいトリガーを作成し、既存のトリガーを単一の文で置き換えることができる本機能について解説します。
$ gem install pgtrigger Usage Create a migration like this class AddTriggerToSomeTable < ActiveRecord::Migration[5.1] def up create_trigger(:table_name, :increase_order, before: [:insert, :update], declare: {var_1: "text := 'test'", var_2: :integer}) do <<-TRIGGERSQL var_2 :=...
If you drop and then recreate a function, the new function is not the same entity as the old; you will have to drop existing rules, views, triggers, etc. that refer to the old function. Use CREATE OR REPLACE FUNCTION to change a function definition without breaking objects...
After providing all required information in theTagstab, selectNext: Review + createto move forward to theReview + createtab, from where you can review all settings configured for your new Azure Database for PostgreSQL flexible server instance, before you trigger its creation: ...
TriggerType UniqueKey UniqueKeyPolicy UnitType UsagesResult VirtualNetworkRule com.azure.resourcemanager.deviceprovisioningservices com.azure.resourcemanager.deviceprovisioningservices.fluent com.azure.resourcemanager.deviceprovisioningservices.models com.azure.resourcemanager.deviceprovisioningservices.fl...
example plgo test .gitignore LICENSE README.md pl.go README MIT license plgo Tool for easily creating PostgreSQL extensions with stored procedures and triggers in golang. It creates wrapper code, PostgreSQL extension files and builds your package. ...