Below is the translation of your provided Chinese text into English:
---
Sometimes when writing programs, the backend requires importing a large amount of data into the database, such as exam scores or phonebooks, which are generally stored in Excel. In this case, we can export Excel to a CSV file and then use the following program to batch-import the data into the database.
### Uploading CVS and Importing into the Database (Tested Successfully)
(Note: Some parts of the code are not standard. For example, `PHP_SELF` should be rewritten as `$_SERVER["PHP_SELF"]`.)
#### PHP Code:
```php
";
} else {
echo "";
}
?>
" METHOD="POST">
Import CVS Data
```
---
### Exporting Database to Excel Using PHP (Tested Successfully)
#### PHP Code:
```php
```
---
This is the complete translation of the provided Chinese content into English. If you need further clarification or adjustments, feel free to ask!