How to see MySqlHook result in log

The MySQL operator currently (airflow 1.10.1 at time of writing) doesn't support returning anything in XCom, so the fix for you, for now, is to write a small operator yourself. You can do this directly in your DAG file:

from airflow.operators.python_operator import PythonOperator
from airflow.operators.mysql_operator import MySqlOperator
from airflow.hooks.mysql_hook import MySqlHook

class ReturningMySqlOperator(MySqlOperator):
    def execute(self, context):
        self.log.info('Executing: %s', self.sql)
        hook = MySqlHook(mysql_conn_id=self.mysql_conn_id,
                         schema=self.database)
        return hook.get_records(
            self.sql,
            parameters=self.parameters)

t1 = ReturningMySqlOperator(
    task_id='basic_mysql',
    mysql_conn_id='airflow_db',
    sql="select * from xcom",
    dag=dag)

def get_records(**kwargs):
    ti = kwargs['ti']
    xcom = ti.xcom_pull(task_ids='basic_mysql')
    string_to_print = 'Value in xcom is: {}'.format(xcom)
    # Get data in your logs
    logging.info(string_to_print)

t2 = PythonOperator(
    task_id='records',
    provide_context=True,
    python_callable=get_records,
    dag=dag)

t1 >> t2

AFAIK, MySqlOperator serves the purpose of running an UPDATE / DELETE etc. query; in other words queries which:

• don't return any result
• return result, but you are not bothered about it

In order to get hold of the actual result, you must exploit MySqlHook. Here's a small code-snippet (Python 3.6+) to get started (not tested, but just for hints)

from typing import List, Optional, Any
from airflow.hooks.mysql_hook import MySqlHook

# instantiate a MySqlHook
mysql_hook: MySqlHook = MySqlHook(mysql_conn_id="airflow_db")

# get records (this method comes from airflow.hooks.db_api_hook.DbApiHook)
records: List[List[Optional[Any]]] = mysql_hook.get_records(sql="select * from xcom")

# print records
print(records)

# alternatively, you can write records to task's logger
# note that here 'operator' = reference to your Operator
# operator.log.info("\n".join(records))

The output of print() / log.info() will appear in tasks's log on the UI

Generally with Airflow your query should be written such that results go into a temp table (maybe including the results_name_{{ds_nodash}}). You can then use the MySqlToSomethingElseOperator to move the temp table's results. Then clean up by dropping the table.

I don't see any reason that logging the results in Airflow logs would be sufficient work for a DAG to do.