docs: update project structure and add database documentation

- Add tests/ directory to .gitignore
- Document database connectivity with pyodbc and config
- Add project structure and file organization guidelines
- Update installation steps to use requirements.txt
- Document new dependencies: pandas, openpyxl, pyodbc

CLAUDE.md

@@ -12,8 +12,8 @@ This is a Python automation project using Playwright to interact with a Chinese
 # Activate the virtual environment (Windows)
 .venv\Scripts\activate
 
-# Install dependencies
-pip install playwright
+# Install all dependencies
+pip install -r requirements.txt
 
 # Install Playwright browsers
 playwright install chromium
@@ -23,17 +23,53 @@ playwright install chromium
 
 ```bash
 # Run the main test script
-python test_playwright.py
+python tests/test_playwright.py
 
 # Run the record script
 python record.py
+
+# Run database query test
+python tests/test_db_query.py
 ```
 
 ## Key Dependencies
 
 - **playwright==1.57.0**: Browser automation framework
+- **pyodbc**: SQL Server database connectivity
+- **pandas**: Data processing and Excel file handling
+- **openpyxl**: Excel file operations
 - Uses synchronous API (`playwright.sync_api`)
 
+## Project Structure
+
+```
+playwrite/
+├── config/              # Configuration files (database, etc.)
+├── db/                  # Database connection components
+├── data/                # Data files (excluded from git)
+├── docs/                # Documentation (e.g., DEPENDENCIES.md)
+├── tests/               # Test scripts (excluded from git)
+├── requirements.txt     # Python dependencies
+├── .gitignore          # Git ignore rules
+└── CLAUDE.md           # This file
+```
+
+## File Organization Rules
+
+**IMPORTANT**: When creating test scripts, always place them in the `tests/` folder:
+
+- Test scripts should be prefixed with `test_`
+- All files in `tests/` are excluded from git tracking
+- Examples: `tests/test_playwright.py`, `tests/test_db_query.py`
+
+**Configuration Management**:
+- Place configuration files in `config/` folder
+- Database credentials and settings go in `config/database_config.py`
+
+**Data Storage**:
+- Use `data/` folder for temporary data files
+- This folder is excluded from git tracking
+
 ## Architecture
 
 ### Nested Iframe Structure
@@ -80,6 +116,35 @@ with page.expect_popup() as popup_info:
 new_page = popup_info.value
 ```
 
+### Database Connection
+
+The project uses `pyodbc` to connect to SQL Server for data queries:
+
+```python
+from db.connection import get_connection
+
+# Using context manager
+with get_connection() as db:
+    results = db.execute_query("SELECT * FROM table")
+    # Connection automatically closed
+
+# Using the query helper
+from db.connection import query_production_orders
+results = query_production_orders(['ID1', 'ID2', 'ID3'])
+```
+
+Database configuration is stored in `config/database_config.py`:
+```python
+SQL_SERVER_CONFIG = {
+    'driver': 'ODBC Driver 18 for SQL Server',
+    'server': '192.168.110.114',
+    'database': 'CompanyDB',
+    'username': 'peng',
+    'password': 'Cqbld123456.',
+    'TrustServerCertificate': 'yes'
+}
+```
+
 ## Common Utilities
 
 ### `get_input_by_label(frame, label_text)`