input: Write a python function to insert PDF metadata and content into a SQLite database.
  assert insert_pdf_data(['file1.pdf', 'file2.pdf', 'file3.pdf']) == True
  assert insert_pdf_data(['file4.pdf', 'file5.pdf']) == True
output: def insert_pdf_data(file_list):
      import sqlite3
      from PyPDF2 import PdfFileReader
      import os
  
      # Create a new SQLite database or connect to an existing one
      conn = sqlite3.connect('pdf_data.db')
      cursor = conn.cursor()
  
      # Create a table to store PDF metadata and content
      cursor.execute('''
          CREATE TABLE IF NOT EXISTS pdf_data (
              id INTEGER PRIMARY KEY AUTOINCREMENT,
              filename TEXT,
              title TEXT,
              author TEXT,
              subject TEXT,
              keywords TEXT,
              content TEXT
          )
      ''')
  
      # Function to extract metadata and content from a PDF file
      def extract_pdf_data(file_path):
          with open(file_path, 'rb') as file:
              reader = PdfFileReader(file)
              info = reader.getDocumentInfo()
              content = ""
              for page_num in range(reader.getNumPages()):
                  content += reader.getPage(page_num).extract_text() + "\n"
              metadata = {
                  'title': info.title if info.title else '',
                  'author': info.author if info.author else '',
                  'subject': info.subject if info.subject else '',
                  'keywords': info.keywords if info.keywords else '',
                  'content': content
              }
          return metadata
  
      try:
          for file in file_list:
              if os.path.exists(file):
                  metadata = extract_pdf_data(file)
                  cursor.execute('''
                      INSERT INTO pdf_data (filename, title, author, subject, keywords, content)
                      VALUES (?, ?, ?, ?, ?, ?)
                  ''', (file, metadata['title'], metadata['author'], metadata['subject'], metadata['keywords'], metadata['content']))
              else:
                  return False
          
          conn.commit()
      except Exception as e:
          conn.rollback()
          return False
      finally:
          conn.close()
  
      return True