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With the advancement in technology, businesses have started to receive invoices in PDF format. Although it has made the invoice processing efficient, it is challenging to extract data from these PDF invoices. But with the help of Python and SQL integration, this task can be accomplished with relative ease. In this blog post, we will discuss how to extract data from PDF invoices using Python and SQL integration, including SQL Server 2012, SQL Server 2014, MySQL 5.6, DB2 10.5, and Azure SQL.

The first step is to extract the text from the PDF invoice. Python offers several libraries to extract text from PDFs, but the most common one is PyPDF2. This Python library reads text from PDF files and can be integrated with SQL to store the extracted data. After installing the PyPDF2 library, you can use the following code to read a PDF file and extract its text.

import PyPDF2


def extract_text_from_pdf(pdf_path):

    with open(pdf_path, 'rb') as file:

        reader = PyPDF2.PdfFileReader(file)

        total_pages = reader.getNumPages()

        text = ''

        for page_number in range(total_pages):

            page = reader.getPage(page_number)

            text += page.extract_text()

    return text

Once we have extracted all the text from the PDF invoice, the next step is to parse the text and extract the relevant data fields. This can be done using Python's regular expression (regex) module. After extracting the necessary fields from the text, we can store this data in our SQL database.

To insert the extracted data into the SQL database, we will use the Python MySQL connector. First, establish a connection to the MySQL database using the connect() function. Then create a cursor object using the cursor() method of the MySQLConnection object. With the cursor object, you can execute any SQL operation. Here is an example of how to insert data into a MySQL database.

import mysql.connector


db_connection = mysql.connector.connect(host='localhost',

                                        database='invoice_db',

                                        user='root',

                                        password='password')

cursor = db_connection.cursor()

insert_query = "INSERT INTO invoices (invoice_number, date, amount) VALUES (%s, %s, %s)"

invoice_data = ('INV123', '2016-07-01', 100.00)

cursor.execute(insert_query, invoice_data)

db_connection.commit()

cursor.close()

db_connection.close()

The above code connects to the MySQL database, executes an INSERT SQL query to insert an invoice's data into the 'invoices' table, and then closes the database connection. The same approach can be used for SQL Server 2012, SQL Server 2014, DB2 10.5, and Azure SQL databases, with the only difference being the connection string and the SQL dialect used.

In conclusion, Python and SQL integration provide a powerful tool for businesses to automate the process of extracting data from PDF invoices and storing it into SQL databases. This not only saves time and reduces the chance of errors, but also allows businesses to easily analyze their invoice data. With the right tools and a bit of coding, it is possible to turn a pile of PDF invoices into valuable business insights.