Replace a domain in a big SQL file

replace.py

#!/usr/bin/env python3
"""
replace.py — Replace a domain in a large SQL file safely and efficiently.

------------------------------------------------------------
USAGE:
    python replace.py <path_to_file.sql> <old_domain> <new_domain>

EXAMPLE:
    python replace.py ./dump.sql old-domain.com newdomain.com

DESCRIPTION:
    This script reads a large .sql file line by line and replaces
    all occurrences of the specified domain. It writes the output
    to a NEW file with a timestamp, leaving the original intact.

NOTES:
    - Recommended to BACK UP your .sql file before running.
    - Not optimized for binary SQL dumps (use plain text).
    - Intended for educational or personal use only.
    - Provided as-is, without warranty of any kind.

AUTHOR:
    Johan Guse
DATE:
    2025-10-15
"""

import re
import os
import sys
import time
from datetime import datetime


def replace_domain_in_large_sql(filename: str, old_domain: str, new_domain: str):
    """Replaces all occurrences of old_domain with new_domain in a large SQL file."""
    if not os.path.exists(filename):
        print(f"❌ Error: File not found: {filename}")
        sys.exit(1)

    start_time = time.time()
    timestamp = datetime.now().strftime("%Y-%m-%d_%H%M%S")

    # Generate output filename based on original
    base, ext = os.path.splitext(filename)
    new_filename = f"{base}_replaced_{timestamp}{ext}"
    count = 0

    try:
        with open(filename, "r", encoding="utf-8", errors="ignore") as file, open(
            new_filename, "w", encoding="utf-8"
        ) as new_file:
            for line in file:
                new_line, replacements = re.subn(old_domain, new_domain, line)
                new_file.write(new_line)
                count += replacements

        elapsed_time = round(time.time() - start_time, 2)
        print(f"✅ Replaced {count} occurrence(s) of '{old_domain}' with '{new_domain}'.")
        print(f"📄 New file saved as: {new_filename}")
        print(f"⏱️ Operation completed in {elapsed_time} seconds.")

    except Exception as e:
        print(f"⚠️ An error occurred: {e}")
        if os.path.exists(new_filename):
            os.remove(new_filename)
        sys.exit(1)


if __name__ == "__main__":
    if len(sys.argv) != 4:
        print("Usage: python replace.py <path_to_file.sql> <old_domain> <new_domain>")
        print("Example: python replace.py ./dump.sql example.com newexample.com")
        sys.exit(1)

    file_path = sys.argv[1]
    old_domain = sys.argv[2]
    new_domain = sys.argv[3]

    replace_domain_in_large_sql(file_path, old_domain, new_domain)