pandassql.py

from sqlalchemy import create_engine
import pandas as pd 

params = urllib.parse.quote_plus(
        r'Driver={ODBC Driver 17 for SQL Server};'
        + fr'Server={sql_server}'
        + fr',1433;Database={sql_db};'
        + fr'Uid={sql_user};Pwd={sql_password};'
        + r'Encrypt=yes;TrustServerCertificate=Yes;Connection Timeout=30;')

conn_str = 'mssql+pyodbc:///?odbc_connect={}'.format(params)
engine = create_engine(conn_str, fast_executemany=True)


## pandas df#

df.to_sql('temp_tbl',schema='dbo',if_exists='replace',index=False,con=engine)


qry = """
SELECT a.ID
     , b.Start_Date
     , b.End_Date
     , a.V1
     , a.V2
     , a.V3
FROM your_tbl    a
  LEFT JOIN test b
    ON a.id = b.id
    AND CAST(a.[Day] AS DATE) BETWEEN
         CAST(b.[Start_Date] AS DATE)
         AND CAST(b.[End_Date] AS DATE)
"""

output = pq.read_sql(qry,engine)

print(output)