Python - How to Skip First Line in CSV?

When working with CSV files in Python, it is common to encounter files that include a header row as the first line. This header typically contains the column names, which you might not want to process as data. In such cases, you can easily skip the first line using the next() method from Python’s built-in csv module. This approach is particularly useful when you want to read and process only the actual data rows, excluding the header.

Let’s explore how to achieve this with a practical example.

Example to Skip First Line While Reading a CSV File in Python

Imagine you have a CSV file named product_record.csv with the following content:

DEPTNO,DNAME,LOC
10,ACCOUNTING,NEW YORK
20,RESEARCH,DALLAS
30,SALES,CHICAGO
40,OPERATIONS,BOSTON

Here, the first line (DEPTNO,DNAME,LOC) is the header row. If you want to read and print only the data rows, you need to skip this header.

To skip the first line while reading the CSV file, you can use the next() function right after creating the CSV reader object. This will advance the reader to the second line, so the header is not included in your data processing loop.

Here’s how you can do it:

import csv

with open("product_record.csv", "r") as csv_file:
    csv_reader = csv.reader(csv_file, delimiter=',')
    # the below statement will skip the first row
    next(csv_reader)
    for lines in csv_reader:
      print(lines)

Output

['10', 'ACCOUNTING', 'NEW YORK']
['20', 'RESEARCH', 'DALLAS']
['30', 'SALES', 'CHICAGO']
['40', 'OPERATIONS', 'BOSTON']

As you can see, the header row is not included in the output. Only the actual data rows are printed.

Why Use next() to Skip the Header in Python?

Using next() is a straightforward and efficient way to skip the first line of a CSV file in Python. This is especially helpful when you are dealing with large files or when you want to avoid processing column names as data. By calling next(csv_reader), you simply move the file pointer past the header, so your subsequent code can focus only on the data rows.

Additional Tips

• If your CSV file does not have a header row, you can omit the next() line.
• This method works for both small and large CSV files, and it is a common practice in data processing tasks.
• If you are using the csv.DictReader class, it automatically uses the first row as the header, so you do not need to skip it manually.

Conclusion

Skipping the first line of a CSV file in Python is easy with the next() function. This simple technique allows you to ignore header rows and work directly with your data. The csv module provides a reliable way to handle CSV files, making your data processing tasks more efficient and organized.

See also:

• Import CSV File into Oracle Table Using Python