plv8 触发器使用

触发器使用

• demo

CREATE FUNCTION test_trigger() RETURNS TRIGGER AS

$

    plv8.elog(NOTICE, "NEW = ", JSON.stringify(NEW));

    plv8.elog(NOTICE, "OLD = ", JSON.stringify(OLD));

    plv8.elog(NOTICE, "TG_OP = ", TG_OP);

    plv8.elog(NOTICE, "TG_ARGV = ", TG_ARGV);

    if (TG_OP == "UPDATE") {

        NEW.i = 102;

        return NEW;

    }

$

LANGUAGE "plv8";

​

CREATE TRIGGER test_trigger

    BEFORE INSERT OR UPDATE OR DELETE

    ON test_tbl FOR EACH ROW

    EXECUTE PROCEDURE test_trigger('foo', 'bar');

• 包含的对象
  基于pg标准提供的参数

 

NEW

OLD

TG_NAME

TG_WHEN

TG_LEVEL

TG_OP

TG_RELID

TG_TABLE_NAME

TG_TABLE_SCHEMA

TG_ARGV

参考：https://www.postgresql.org/docs/current/static/plpgsql-trigger.html

参考资料

https://www.postgresql.org/docs/current/plpgsql-trigger.html
https://plv8.github.io/