SQLExecuteQueryOperator for Snowflake¶
Use the SQLExecuteQueryOperator to execute
SQL commands in a Snowflake database.
Using the Operator¶
Use the conn_id argument to connect to your Snowflake instance where
the connection metadata is structured as follows:
Parameter |
Input |
|---|---|
Login: string |
Snowflake user name |
Password: string |
Password for Snowflake user |
Schema: string |
Set schema to execute SQL operations on by default |
Extra: dictionary |
|
An example usage of the SQLExecuteQueryOperator to connect to Snowflake is as follows:
snowflake_op_sql_str = SQLExecuteQueryOperator(
task_id="snowflake_op_sql_str", sql=CREATE_TABLE_SQL_STRING
)
snowflake_op_with_params = SQLExecuteQueryOperator(
task_id="snowflake_op_with_params",
sql=SQL_INSERT_STATEMENT,
parameters={"id": 56},
)
snowflake_op_sql_list = SQLExecuteQueryOperator(task_id="snowflake_op_sql_list", sql=SQL_LIST)
snowflake_op_sql_multiple_stmts = SQLExecuteQueryOperator(
task_id="snowflake_op_sql_multiple_stmts",
sql=SQL_MULTIPLE_STMTS,
split_statements=True,
)
snowflake_op_template_file = SQLExecuteQueryOperator(
task_id="snowflake_op_template_file",
sql="example_snowflake_snowflake_op_template_file.sql",
)
# Create and populate a small dataset for the data quality operator examples.
# We insert one row for `ds` and one for `ds - 1`, each with value = 4.
create_check_table = SQLExecuteQueryOperator(
task_id="create_check_table",
sql=CREATE_CHECK_TABLE_SQL_STRING,
)
populate_check_table = SQLExecuteQueryOperator(
task_id="populate_check_table",
sql=SQL_CHECK_TABLE_INSERT,
)
Note
Parameters that can be passed onto the operator will be given priority over the parameters already given
in the Airflow connection metadata (such as schema, role, database and so forth).
SnowflakeCheckOperator¶
To perform checks against Snowflake you can use
SnowflakeCheckOperator
This operator expects a SQL query that will return a single row. Each value on
that first row is evaluated using Python bool casting. If any of the values
return False the check fails and errors out.
snowflake_check = SnowflakeCheckOperator(
task_id="snowflake_check",
sql=f"SELECT COUNT(*) FROM {SNOWFLAKE_CHECK_TABLE} WHERE ds = TO_DATE('{{{{ ds }}}}')",
)
SnowflakeValueCheckOperator¶
To perform a simple value check using SQL code you can use
SnowflakeValueCheckOperator
This operator expects a SQL query that will return a single row. That value is
evaluated against pass_value, which can be either a string or numeric value.
If numeric, you can also specify tolerance.
snowflake_value_check = SnowflakeValueCheckOperator(
task_id="snowflake_value_check",
sql=f"SELECT SUM(value) FROM {SNOWFLAKE_CHECK_TABLE} WHERE ds = TO_DATE('{{{{ ds }}}}')",
pass_value=4,
)
SnowflakeIntervalCheckOperator¶
To check that the values of metrics given as SQL expressions are within a certain
tolerance of the ones from days_back before you can use
SnowflakeIntervalCheckOperator
snowflake_interval_check = SnowflakeIntervalCheckOperator(
task_id="snowflake_interval_check",
table=SNOWFLAKE_CHECK_TABLE,
metrics_thresholds={"COUNT(*)": 1.5},
days_back=1,
)
SnowflakeSqlApiOperator¶
Use the SnowflakeSqlApiHook to execute
SQL commands in a Snowflake database.
You can also run this operator in deferrable mode by setting deferrable param to True.
This will ensure that the task is deferred from the Airflow worker slot and polling for the task status happens on the trigger.
Using the Operator¶
Use the snowflake_conn_id argument to connect to your Snowflake instance where
the connection metadata is structured as follows:
Parameter |
Input |
|---|---|
Login: string |
Snowflake user name. If using OAuth connection this is the |
Password: string |
Password for Snowflake user. If using OAuth this is the |
Schema: string |
Set schema to execute SQL operations on by default |
Extra: dictionary |
|
An example usage of the SnowflakeSqlApiHook is as follows:
snowflake_sql_api_op_sql_multiple_stmt = SnowflakeSqlApiOperator(
task_id="snowflake_op_sql_multiple_stmt",
sql=SQL_MULTIPLE_STMTS,
statement_count=len(SQL_LIST),
)
Note
Parameters that can be passed onto the operator will be given priority over the parameters already given
in the Airflow connection metadata (such as schema, role, database and so forth).
Durable execution¶
SnowflakeSqlApiOperator submits one or more SQL statements and then polls their statement
handles to completion on the worker. By default the operator runs in a durable mode that makes
this crash-safe: the statement handles are persisted to task state store before polling begins, so if the worker crashes
or is preempted and the task is retried, the operator reconnects to the statements that are
already executing in Snowflake instead of resubmitting the SQL.
On retry the operator checks the prior statements’ state:
if any handle is still running, the operator reconnects and continues polling – handles that already finished are not re-run, only the ones still in progress are waited on
if every handle already succeeded, the operator returns immediately without resubmitting
if any handle failed, or a handle has expired past Snowflake’s retention window, the operator submits the SQL fresh
Because Snowflake’s SQL API has no way to retry or repair a single failed statement within a multi-statement request, a genuine failure always resubmits the whole request batch, matching the operator’s all-or-nothing submission semantics.
Durable execution requires Airflow 3.3 or newer, since it relies on the task state store. On earlier Airflow versions the flag is a no-op and the operator always submits fresh SQL on retry, exactly as before. If the task state store is unavailable at runtime, the operator logs that crash recovery is disabled and behaves the same way.
To opt out and always submit fresh SQL on retry, set durable=False:
api_operator = SnowflakeSqlApiOperator(
task_id="snowflake_sql_api",
snowflake_conn_id="snowflake_default",
sql="select * from table",
statement_count=1,
durable=False,
)
Durable execution applies to the synchronous path. When deferrable=True is set, the Triggerer
already tracks the statement handles across the wait, so deferrable mode takes precedence and
durable has no effect.