在使用 Airflow 的 Snowflake Operator 执行多个 SQL 语句时,需要使用 Snowflake 的事务控制功能来确保事务的原子性。具体实现方法是在 SQL 语句中使用 BEGIN、COMMIT 和 ROLLBACK 语句来开启、提交和回滚事务。代码示例如下:
from airflow.providers.snowflake.operators.snowflake import SnowflakeOperator
with dag:
start_txn = SnowflakeOperator(
task_id='start_transaction',
sql='BEGIN',
snowflake_conn_id='snowflake_conn',
autocommit=False
)
insert_op1 = SnowflakeOperator(
task_id='insert_op1',
sql='INSERT INTO table1 VALUES(1, "value1")',
snowflake_conn_id='snowflake_conn',
autocommit=False
)
insert_op2 = SnowflakeOperator(
task_id='insert_op2',
sql='INSERT INTO table2 VALUES(2, "value2")',
snowflake_conn_id='snowflake_conn',
autocommit=False
)
commit_txn = SnowflakeOperator(
task_id='commit_transaction',
sql='COMMIT',
snowflake_conn_id='snowflake_conn',
autocommit=False
)
rollback_txn = SnowflakeOperator(
task_id='rollback_transaction',
sql='ROLLBACK',
snowflake_conn_id='snowflake_conn',
autocommit=False
)
start_txn >> [insert_op1, insert_op2] >> commit_txn
[insert_op1, insert_op2] >> rollback_txn
代码中使用 SnowflakeOperator 执行 SQL 语句,并通过 autocommit=False 关闭自动提交功能。通过将多个 SnowflakeOperator 串联在一起,并使用 BEGIN、COMMIT 和 ROLLBACK 语句来控制事务的开启、提交和回滚,从而实现事务的原子性。