use formula

src/modules/order/entities/order-item.entity.ts

@@ -1,4 +1,4 @@
-import { Entity, Index, ManyToOne, PrimaryKey, Property } from '@mikro-orm/core';
+import { Entity, Formula, Index, ManyToOne, PrimaryKey, Property } from '@mikro-orm/core';
 import { BaseEntity } from '../../../common/entities/base.entity';
 import { Order } from './order.entity';
 import { Product } from 'src/modules/product/entities/product.entity';
@@ -8,6 +8,7 @@ import { IAttribute } from '../interface/order.interface';
 @Entity({ tableName: 'order_items' })
 @Index({ properties: ['order'] })
 export class OrderItem extends BaseEntity {
+  
   @PrimaryKey({ type: 'bigint', autoincrement: true })
   id: bigint
 
@@ -26,16 +27,19 @@ export class OrderItem extends BaseEntity {
   @Property({ type: 'decimal', precision: 10, scale: 0, nullable: true, })
   unitPrice?: number;
 
-  get subTotal(): number {
+  @Formula(alias => `
-    return Number(this.unitPrice) * (this.quantity)
+    COALESCE(${alias}.unit_price, 0) * ${alias}.quantity
-  }
+  `)
+  subTotal!: number;
 
   @Property({ type: 'decimal', precision: 10, scale: 0, nullable: true })
   discount?: number;
 
-  get total(): number {
+  @Formula(alias => `
-    return Number(this.subTotal) - Number(this.discount || 0)
+    (COALESCE(${alias}.unit_price, 0) * ${alias}.quantity)
-  }
+    - COALESCE(${alias}.discount, 0)
+  `)
+  total!: number;
 
   @Property({ type: 'text', nullable: true })
   description?: string;

src/modules/order/entities/order.entity.ts

@@ -10,7 +10,8 @@ import {
   PrimaryKey,
   BeforeCreate,
   type EventArgs,
-  OptionalProps
+  OptionalProps,
+  Formula
 } from '@mikro-orm/core';
 import { OrderStatusEnum } from '../interface/order.interface';
 import { User } from '../../user/entities/user.entity';
@@ -25,7 +26,7 @@ import { PaymentStatusEnum } from 'src/modules/payment/interface/payment';
 @Index({ properties: ['status'] })
 export class Order {
   [OptionalProps]?: 'createdAt' | 'deletedAt' | 'balance' | 'paidAmount'
-   | 'discount' | 'subTotal' | 'total' | 'taxAmount';
+    | 'discount' | 'subTotal' | 'total' | 'taxAmount';
 
   @PrimaryKey({ type: 'string', columnType: 'char(26)' })
   id: string = ulid()
@@ -61,34 +62,76 @@ export class Order {
 
   // @Property({ type: 'decimal', precision: 10, scale: 0, default: null, nullable: true })
   // discount?: number;
-  get discount(): number {
+  @Formula(alias => `
-    if (!this.items.isInitialized()) return 0;
+    (
-    return this.items
+      SELECT COALESCE(SUM(oi.discount), 0)
-      .getItems()
+      FROM order_items oi
-      .reduce((sum, p) => sum + Number(p.discount), 0);
+      WHERE oi.order_id = ${alias}.id
-  }
+    )
+  `)
+  discount!: number;
+
 
   // @Property({ type: 'decimal', precision: 10, scale: 0, default: null, nullable: true })
   // subTotal?: number;
-  get subTotal(): number {
+  @Formula(alias => `
-    if (!this.items.isInitialized()) return 0;
+    (
-    return this.items
+      SELECT COALESCE(SUM(oi.sub_total), 0)
-      .getItems()
+      FROM order_items oi
-      .reduce((sum, p) => sum + Number(p.subTotal), 0)
+      WHERE oi.order_id = ${alias}.id
-  }
+    )
+  `)
+  subTotal!: number;
+
 
   // @Property({ type: 'decimal', precision: 10, scale: 0, default: null, nullable: true })
   // taxAmount?: number;
-  get taxAmount(): number {
+  @Formula(alias => `
-    return this.enableTax ? this.total * 0.1 : 0
+    (
-  }
+      CASE
+        WHEN ${alias}.enable_tax = true THEN
+          (
+            SELECT COALESCE(SUM(oi.sub_total), 0)
+            FROM order_items oi
+            WHERE oi.order_id = ${alias}.id
+          ) * 0.1
+        ELSE 0
+      END
+    )
+  `)
+  taxAmount!: number;
+
 
 
   // @Property({ type: 'decimal', precision: 10, scale: 0, default: null, nullable: true })
   // total?: number;
-  get total(): number {
+  @Formula(alias => `
-    return this.subTotal - this.discount + Number(this.taxAmount)
+    (
-  }
+      (
+        SELECT COALESCE(SUM(oi.sub_total), 0)
+        FROM order_items oi
+        WHERE oi.order_id = ${alias}.id
+      )
+      -
+      (
+        SELECT COALESCE(SUM(oi.discount), 0)
+        FROM order_items oi
+        WHERE oi.order_id = ${alias}.id
+      )
+      +
+      CASE
+        WHEN ${alias}.enable_tax = true THEN
+          (
+            SELECT COALESCE(SUM(oi.sub_total), 0)
+            FROM order_items oi
+            WHERE oi.order_id = ${alias}.id
+          ) * 0.1
+        ELSE 0
+      END
+    )
+  `)
+  total!: number;
+
 
   // @Property({ type: 'decimal', precision: 10, scale: 0, default: null, nullable: true })
   // paidAmount?: number;
@@ -100,19 +143,53 @@ export class Order {
   // }
 
 
-  get paidAmount(): number {
+  @Formula(alias => `
-    if (!this.payments.isInitialized()) return 0;
+    (
+      SELECT COALESCE(SUM(p.amount), 0)
+      FROM payments p
+      WHERE p.order_id = ${alias}.id
+        AND p.status = '${PaymentStatusEnum.Paid}'
+    )
+  `)
+  paidAmount!: number;
 
-    return this.payments
-      .getItems()
-      .filter(p => p.status == PaymentStatusEnum.Paid)
-      .reduce((sum, p) => sum + Number(p.amount), 0);
-  }
 
-  get balance(): number {
+  @Formula(alias => `
-    const total = Number(this.total ?? 0);
+    (
-    return total - this.paidAmount;
+      (
-  }
+        (
+          SELECT COALESCE(SUM(oi.sub_total), 0)
+          FROM order_items oi
+          WHERE oi.order_id = ${alias}.id
+        )
+        -
+        (
+          SELECT COALESCE(SUM(oi.discount), 0)
+          FROM order_items oi
+          WHERE oi.order_id = ${alias}.id
+        )
+        +
+        CASE
+          WHEN ${alias}.enable_tax = true THEN
+            (
+              SELECT COALESCE(SUM(oi.sub_total), 0)
+              FROM order_items oi
+              WHERE oi.order_id = ${alias}.id
+            ) * 0.1
+          ELSE 0
+        END
+      )
+      -
+      (
+        SELECT COALESCE(SUM(p.amount), 0)
+        FROM payments p
+        WHERE p.order_id = ${alias}.id
+          AND p.status = '${PaymentStatusEnum.Paid}'
+      )
+    )
+  `)
+  balance!: number;
+
 
   @Property({ type: 'int', nullable: true })
   estimatedDays?: number; // number of days to be done