如何计算一列中的行数，但在计算数据存储时不包含空值？

SELECT COUNT(column_name) FROM table_name WHERE column_name IS NOT NULL;

SELECT COUNT(column_name) FROM table_name WHERE column_name IS NOT NULL;

SELECT COUNT(column_name) FROM table_name WHERE column_name IS NOT NULL;

SELECT COUNT(column_name) FROM table_name WHERE column_name IS NOT NULL;

from sqlalchemy import create_engine, Table, MetaData, select

engine = create_engine('your_database_connection_string')
metadata = MetaData(bind=engine)
table = Table('table_name', metadata, autoload_with=engine)

stmt = select([func.count(table.c.column_name)]).where(table.c.column_name.isnot(None))
with engine.connect() as connection:
    result = connection.execute(stmt).fetchone()
    print(result[0])