From 33c3209e875d92ff40301d4d52ce2b4acab3767f Mon Sep 17 00:00:00 2001
From: adis azhar <adisazhar123@gmail.com>
Date: Wed, 15 May 2019 02:24:09 +0700
Subject: [PATCH 1/3] Added adterDestroy lifecycle example

---
 concepts/ORM/Lifecyclecallbacks.md | 55 ++++++++++++++++++++++++++++++
 1 file changed, 55 insertions(+)

diff --git a/concepts/ORM/Lifecyclecallbacks.md b/concepts/ORM/Lifecyclecallbacks.md
index 9dc018bd5..8fb6433c6 100644
--- a/concepts/ORM/Lifecyclecallbacks.md
+++ b/concepts/ORM/Lifecyclecallbacks.md
@@ -64,6 +64,61 @@ module.exports = {
   }
   
 };
+```
+
+If you want to delete child objects after deleting its parent, you can use the `afterDestroy` lifecycle callback. Be careful when using this, as you may lose sensitive data! In this example we will have 2 Models. `Invoice` and `Item`. `Invoice` to `Item` corresponds to `One-to-many` association relation. See [One-to-many associations](https://sailsjs.com/documentation/concepts/models-and-orm/associations/one-to-many).
+
+```javascript
+// Invoice.js
+
+module.exports = {
+  attributes: {
+    client_name: { type: 'string', required: true },
+    client_email: { type: 'string', required: false },
+    project_name: { type: 'string', required: true },
+    project_description: { type: 'string', required: false },
+    invoice_status: { type: 'string', defaultsTo: 'unpaid' },
+    due_date: { type: 'string', required: false },
+    total_price: { type: 'number', required: true},
+    items: {
+      collection: 'item',
+      via: 'invoice'
+    },
+    user: {
+      model: 'user'
+    }
+  },
+
+  async beforeDestroy(criteria, proceed) {
+    try {
+      // destroy items related to parent
+      // we can access the deleted parent object using 
+      // criteria object
+      await Item.destroy({invoice: criteria.where.id});      
+    } catch (error) {
+      return proceed(error);
+    }
+    return proceed();
+  }
+
+};
+
+
+// Item.js
+
+module.exports = {
+
+  attributes: {
+    name: { type: 'string', required: true },
+    price: { type: 'number', columnType: 'float', required: false },
+    invoice: {
+      model: 'invoice'
+    }
+  },
+};
+
+
+
 ```
 
 

From 626fc3b03c287a203b12dd348f4d840f7da582aa Mon Sep 17 00:00:00 2001
From: adis azhar <adisazhar123@gmail.com>
Date: Wed, 15 May 2019 02:32:37 +0700
Subject: [PATCH 2/3] Added afterDestroy lifecycle example

---
 concepts/ORM/Lifecyclecallbacks.md | 18 +++++++++++++++---
 1 file changed, 15 insertions(+), 3 deletions(-)

diff --git a/concepts/ORM/Lifecyclecallbacks.md b/concepts/ORM/Lifecyclecallbacks.md
index 8fb6433c6..bb76a24b5 100644
--- a/concepts/ORM/Lifecyclecallbacks.md
+++ b/concepts/ORM/Lifecyclecallbacks.md
@@ -83,9 +83,6 @@ module.exports = {
     items: {
       collection: 'item',
       via: 'invoice'
-    },
-    user: {
-      model: 'user'
     }
   },
 
@@ -118,6 +115,21 @@ module.exports = {
 };
 
 
+// Delete Invoice Action
+
+  deleteInvoice: async(req, res) => {
+    let invoice;
+    try {
+      //invoice_id is parameter send by client
+      invoice = await Invoice.destroy({id: req.param('invoice_id')}); 
+    } catch (error) {
+      console.log(error);
+      return false;
+    }
+    return res.status(202).json({message: 'invoice deleted'});
+  },
+
+
 
 ```
 

From 6da52c0b75e7d43dfeafb59d5dbcac4e4eb3aba6 Mon Sep 17 00:00:00 2001
From: adis azhar <adisazhar123@gmail.com>
Date: Wed, 15 May 2019 02:36:02 +0700
Subject: [PATCH 3/3] Added beforeDestroy lifecycle example [revision of
 previous commit]

---
 concepts/ORM/Lifecyclecallbacks.md | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/concepts/ORM/Lifecyclecallbacks.md b/concepts/ORM/Lifecyclecallbacks.md
index bb76a24b5..7050028ec 100644
--- a/concepts/ORM/Lifecyclecallbacks.md
+++ b/concepts/ORM/Lifecyclecallbacks.md
@@ -66,7 +66,7 @@ module.exports = {
 };
 ```
 
-If you want to delete child objects after deleting its parent, you can use the `afterDestroy` lifecycle callback. Be careful when using this, as you may lose sensitive data! In this example we will have 2 Models. `Invoice` and `Item`. `Invoice` to `Item` corresponds to `One-to-many` association relation. See [One-to-many associations](https://sailsjs.com/documentation/concepts/models-and-orm/associations/one-to-many).
+If you want to delete child objects when deleting its parent, you can use the `beforeDestroy` lifecycle callback. By using `beforeDestory` lifecycle, it will delete the child objects before the parent is deleted. You can stimulate a `cascade on delete` with this. Be careful when using this, as you may lose sensitive data! In this example we will have 2 Models. `Invoice` and `Item`. `Invoice` to `Item` corresponds to `One-to-many` association relation. See [One-to-many associations](https://sailsjs.com/documentation/concepts/models-and-orm/associations/one-to-many).
 
 ```javascript
 // Invoice.js