# Walkthrough - PostgreSQL Compatibility Fixes

I have resolved the 500 Internal Server Error encountered when fetching dashboard data. The issue was caused by MySQL-specific SQL syntax in the backend controllers, which is incompatible with your PostgreSQL database.

## Changes Made

### Backend API

#### 1. Statistics Controller Fix
Updated [StatisticsController.php](file:///media/itc43/Data/OTHER_PROJECT/kulakpos/kulakpos_15Maret2026_to%20GTEA/public_html/app/Http/Controllers/Api/StatisticsController.php) to use PostgreSQL's `TO_CHAR` function and **double-quoted camelCase column names** like `"totalAmount"`.

**Before:**
```php
$sales_data = Sale::selectRaw("DATE_FORMAT(created_at, '%Y-%m-%d') as date, SUM(totalAmount) as amount")
```

**After:**
```php
$sales_data = Sale::selectRaw("TO_CHAR(created_at, 'YYYY-MM-DD') as date, SUM(\"totalAmount\") as amount")
```

#### 2. Report Controller Fix
Updated [AcnooReportController.php](file:///media/itc43/Data/OTHER_PROJECT/kulakpos/kulakpos_15Maret2026_to%20GTEA/public_html/app/Http/Controllers/Api/AcnooReportController.php) to use the PostgreSQL cast operator `::date` and quoted camelCase columns (`"saleDate"`, `"lossProfit"`, etc.).

**Example After:**
```php
DB::raw('"saleDate"::date as date')
DB::raw('SUM("lossProfit") as total_sale_income')
```

#### 3. Other Database Compatibility Fixes
- **Admin Dashboard:** Replaced `MONTHNAME()` with `TO_CHAR(..., 'Month')` in [DashboardController.php](file:///media/itc43/Data/OTHER_PROJECT/kulakpos/kulakpos_15Maret2026_to%20GTEA/public_html/app/Http/Controllers/Admin/DashboardController.php).
- **Transfer Model:** Replaced `CAST(... AS UNSIGNED)` with `CAST(... AS INTEGER)` in [Transfer.php](file:///media/itc43/Data/OTHER_PROJECT/kulakpos/kulakpos_15Maret2026_to%20GTEA/public_html/app/Models/Transfer.php).

## Verification Results

### Manual Verification Required
As the backend environment is restricted, please perform the following steps to verify the fix:
1. Ensure your PostgreSQL database is running.
2. Restart your Laravel development server: `php artisan serve`.
3. Run your Flutter application and navigate to the dashboard.
4. Verify that the "Failed to fetch business data 500" error no longer appears and that data is displayed correctly.