to be delete

delete.py

import pandas as pd
from sqlalchemy import create_engine
from sqlalchemy.engine import URL
from concurrent.futures import ThreadPoolExecutor

# Sample DataFrame
data = {
    'col1': range(100),
    'col2': range(100, 200)
}
df = pd.DataFrame(data)

# MSSQL connection setup
connection_string = URL.create(
    "mssql+pyodbc",
    username="your_username",
    password="your_password",
    host="your_host",
    port=1433,
    database="your_database",
    query={"driver": "ODBC Driver 17 for SQL Server"},
)
engine = create_engine(connection_string)

# Define chunk size
chunk_size = 20

# Split DataFrame into chunks
chunks = [df[i:i + chunk_size] for i in range(0, len(df), chunk_size)]

# Function to insert a chunk into the database
def insert_chunk(chunk, table_name, if_exists_option):
    chunk.to_sql(
        name=table_name,
        con=engine,
        if_exists=if_exists_option,
        index=False
    )

# Multithreading insertion
def insert_chunks_multithreaded(chunks, table_name):
    with ThreadPoolExecutor() as executor:
        futures = []
        for i, chunk in enumerate(chunks):
            if_exists_option = 'replace' if i == 0 else 'append'
            futures.append(
                executor.submit(insert_chunk, chunk, table_name, if_exists_option)
            )
        # Ensure all threads complete
        for future in futures:
            future.result()

# Call the function
insert_chunks_multithreaded(chunks, "your_table_name")