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PyAthena
PyAthena is a Python DB API 2.0 (PEP 249)
_ client for Amazon Athena
_.
.. _DB API 2.0 (PEP 249)
: https://www.python.org/dev/peps/pep-0249/
.. _Amazon Athena
: https://docs.aws.amazon.com/athena/latest/APIReference/Welcome.html
Requirements
-
Python
- CPython 3.6, 3.7 3.8 3.9
Installation
.. code:: bash
$ pip install PyAthena
Extra packages:
+---------------+--------------------------------------+------------------+
| Package | Install command | Version |
+===============+======================================+==================+
| Pandas | pip install PyAthena[Pandas]
| >=1.0.0 |
+---------------+--------------------------------------+------------------+
| SQLAlchemy | pip install PyAthena[SQLAlchemy]
| >=1.0.0, <2.0.0 |
+---------------+--------------------------------------+------------------+
Usage
Basic usage
.. code:: python
from pyathena import connect
cursor = connect(s3_staging_dir="s3://YOUR_S3_BUCKET/path/to/",
region_name="us-west-2").cursor()
cursor.execute("SELECT * FROM one_row")
print(cursor.description)
print(cursor.fetchall())
Cursor iteration
.. code:: python
from pyathena import connect
cursor = connect(s3_staging_dir="s3://YOUR_S3_BUCKET/path/to/",
region_name="us-west-2").cursor()
cursor.execute("SELECT * FROM many_rows LIMIT 10")
for row in cursor:
print(row)
Query with parameter
Supported `DB API paramstyle`_ is only ``PyFormat``.
``PyFormat`` only supports `named placeholders`_ with old ``%`` operator style and parameters specify dictionary format.
.. code:: python
from pyathena import connect
cursor = connect(s3_staging_dir="s3://YOUR_S3_BUCKET/path/to/",
region_name="us-west-2").cursor()
cursor.execute("""
SELECT col_string FROM one_row_complex
WHERE col_string = %(param)s
""", {"param": "a string"})
print(cursor.fetchall())
if ``%`` character is contained in your query, it must be escaped with ``%%`` like the following:
.. code:: sql
SELECT col_string FROM one_row_complex
WHERE col_string = %(param)s OR col_string LIKE 'a%%'
.. _`DB API paramstyle`: https://www.python.org/dev/peps/pep-0249/#paramstyle
.. _`named placeholders`: https://pyformat.info/#named_placeholders
SQLAlchemy
~~~~~~~~~~
Install SQLAlchemy with ``pip install "SQLAlchemy>=1.0.0, <2.0.0"`` or ``pip install PyAthena[SQLAlchemy]``.
Supported SQLAlchemy is 1.0.0 or higher and less than 2.0.0.
.. code:: python
from urllib.parse import quote_plus # PY2: from urllib import quote_plus
from sqlalchemy.engine import create_engine
from sqlalchemy.sql.expression import select
from sqlalchemy.sql.functions import func
from sqlalchemy.sql.schema import Table, MetaData
conn_str = "awsathena+rest://{aws_access_key_id}:{aws_secret_access_key}@athena.{region_name}.amazonaws.com:443/"\
"{schema_name}?s3_staging_dir={s3_staging_dir}""
engine = create_engine(conn_str.format(
aws_access_key_id=quote_plus("YOUR_ACCESS_KEY_ID"),
aws_secret_access_key=quote_plus("YOUR_SECRET_ACCESS_KEY"),
region_name="us-west-2",
schema_name="default",
s3_staging_dir=quote_plus("s3://YOUR_S3_BUCKET/path/to/")))
many_rows = Table("many_rows", MetaData(bind=engine), autoload=True)
print(select([func.count("*")], from_obj=many_rows).scalar())
The connection string has the following format:
.. code:: text
awsathena+rest://{aws_access_key_id}:{aws_secret_access_key}@athena.{region_name}.amazonaws.com:443/{schema_name}?s3_staging_dir={s3_staging_dir}&...
If you do not specify ``aws_access_key_id`` and ``aws_secret_access_key`` using instance profile or boto3 configuration file:
.. code:: text
awsathena+rest://:@athena.{region_name}.amazonaws.com:443/{schema_name}?s3_staging_dir={s3_staging_dir}&...
NOTE: ``s3_staging_dir`` requires quote. If ``aws_access_key_id``, ``aws_secret_access_key`` and other parameter contain special characters, quote is also required.
Pandas
~~~~~~
As DataFrame
^^^^^^^^^^^^
You can use the `pandas.read_sql`_ to handle the query results as a `DataFrame object`_.
.. code:: python
from pyathena import connect
import pandas as pd
conn = connect(s3_staging_dir="s3://YOUR_S3_BUCKET/path/to/",
region_name="us-west-2")
df = pd.read_sql("SELECT * FROM many_rows", conn)
print(df.head())
The ``pyathena.pandas.util`` package also has helper methods.
.. code:: python
from pyathena import connect
from pyathena.pandas.util import as_pandas
cursor = connect(s3_staging_dir="s3://YOUR_S3_BUCKET/path/to/",
region_name="us-west-2").cursor()
cursor.execute("SELECT * FROM many_rows")
df = as_pandas(cursor)
print(df.describe())
If you want to use the query results output to S3 directly, you can use `PandasCursor`_.
This cursor fetches query results faster than the default cursor. (See `benchmark results`_.)
.. _`pandas.read_sql`: https://pandas.pydata.org/pandas-docs/stable/reference/api/pandas.read_sql.html
.. _`benchmark results`: benchmarks/README.rst
To SQL
^^^^^^
You can use `pandas.DataFrame.to_sql`_ to write records stored in DataFrame to Amazon Athena.
`pandas.DataFrame.to_sql`_ uses `SQLAlchemy`_, so you need to install it.
.. code:: python
import pandas as pd
from urllib.parse import quote_plus
from sqlalchemy import create_engine
conn_str = "awsathena+rest://:@athena.{region_name}.amazonaws.com:443/"\
"{schema_name}?s3_staging_dir={s3_staging_dir}&s3_dir={s3_dir}&compression=snappy"
engine = create_engine(conn_str.format(
region_name="us-west-2",
schema_name="YOUR_SCHEMA",
s3_staging_dir=quote_plus("s3://YOUR_S3_BUCKET/path/to/"),
s3_dir=quote_plus("s3://YOUR_S3_BUCKET/path/to/")))
df = pd.DataFrame({"a": [1, 2, 3, 4, 5]})
df.to_sql("YOUR_TABLE", engine, schema="YOUR_SCHEMA", index=False, if_exists="replace", method="multi")
The location of the Amazon S3 table is specified by the ``s3_dir`` parameter in the connection string.
If ``s3_dir`` is not specified, ``s3_staging_dir`` parameter will be used. The following rules apply.
.. code:: text
s3://{s3_dir or s3_staging_dir}/{schema}/{table}/
The data format only supports Parquet. The compression format is specified by the ``compression`` parameter in the connection string.
The ``pyathena.pandas.util`` package also has helper methods.
.. code:: python
import pandas as pd
from pyathena import connect
from pyathena.pandas.util import to_sql
conn = connect(s3_staging_dir="s3://YOUR_S3_BUCKET/path/to/",
region_name="us-west-2")
df = pd.DataFrame({"a": [1, 2, 3, 4, 5]})
to_sql(df, "YOUR_TABLE", conn, "s3://YOUR_S3_BUCKET/path/to/",
schema="YOUR_SCHEMA", index=False, if_exists="replace")
This helper method supports partitioning.
.. code:: python
import pandas as pd
from datetime import date
from pyathena import connect
from pyathena.pandas.util import to_sql
conn = connect(s3_staging_dir="s3://YOUR_S3_BUCKET/path/to/",
region_name="us-west-2")
df = pd.DataFrame({
"a": [1, 2, 3, 4, 5],
"dt": [
date(2020, 1, 1), date(2020, 1, 1), date(2020, 1, 1),
date(2020, 1, 2),
date(2020, 1, 3)
],
})
to_sql(df, "YOUR_TABLE", conn, "s3://YOUR_S3_BUCKET/path/to/",
schema="YOUR_SCHEMA", partitions=["dt"])
cursor = conn.cursor()
cursor.execute("SHOW PARTITIONS YOUR_TABLE")
print(cursor.fetchall())
Conversion to Parquet and upload to S3 use `ThreadPoolExecutor`_ by default.
It is also possible to use `ProcessPoolExecutor`_.
.. code:: python
import pandas as pd
from concurrent.futures.process import ProcessPoolExecutor
from pyathena import connect
from pyathena.pandas.util import to_sql
conn = connect(s3_staging_dir="s3://YOUR_S3_BUCKET/path/to/",
region_name="us-west-2")
df = pd.DataFrame({"a": [1, 2, 3, 4, 5]})
to_sql(df, "YOUR_TABLE", conn, "s3://YOUR_S3_BUCKET/path/to/",
schema="YOUR_SCHEMA", index=False, if_exists="replace",
chunksize=1, executor_class=ProcessPoolExecutor, max_workers=5)
.. _`pandas.DataFrame.to_sql`: https://pandas.pydata.org/pandas-docs/stable/reference/api/pandas.DataFrame.to_sql.html
.. _`ThreadPoolExecutor`: https://docs.python.org/3/library/concurrent.futures.html#threadpoolexecutor
.. _`ProcessPoolExecutor`: https://docs.python.org/3/library/concurrent.futures.html#processpoolexecutor
DictCursor
~~~~~~~~~~
DictCursor retrieve the query execution result as a dictionary type with column names and values.
You can use the DictCursor by specifying the ``cursor_class``
with the connect method or connection object.
.. code:: python
from pyathena import connect
from pyathena.cursor import DictCursor
cursor = connect(s3_staging_dir="s3://YOUR_S3_BUCKET/path/to/",
region_name="us-west-2",
cursor_class=DictCursor).cursor()
.. code:: python
from pyathena.connection import Connection
from pyathena.cursor import DictCursor
cursor = Connection(s3_staging_dir="s3://YOUR_S3_BUCKET/path/to/",
region_name="us-west-2",
cursor_class=DictCursor).cursor()
It can also be used by specifying the cursor class when calling the connection object's cursor method.
.. code:: python
from pyathena import connect
from pyathena.cursor import DictCursor
cursor = connect(s3_staging_dir="s3://YOUR_S3_BUCKET/path/to/",
region_name="us-west-2").cursor(DictCursor)
.. code:: python
from pyathena.connection import Connection
from pyathena.cursor import DictCursor
cursor = Connection(s3_staging_dir="s3://YOUR_S3_BUCKET/path/to/",
region_name="us-west-2").cursor(DictCursor)
The basic usage is the same as the Cursor.
.. code:: python
from pyathena.connection import Connection
from pyathena.cursor import DictCursor
cursor = Connection(s3_staging_dir="s3://YOUR_S3_BUCKET/path/to/",
region_name="us-west-2").cursor(DictCursor)
cursor.execute("SELECT * FROM many_rows LIMIT 10")
for row in cursor:
print(row["a"])
If you want to change the dictionary type (e.g., use OrderedDict), you can specify like the following.
.. code:: python
from collections import OrderedDict
from pyathena import connect
from pyathena.cursor import DictCursor
cursor = connect(s3_staging_dir="s3://YOUR_S3_BUCKET/path/to/",
region_name="us-west-2",
cursor_class=DictCursor).cursor(dict_type=OrderedDict)
.. code:: python
from collections import OrderedDict
from pyathena import connect
from pyathena.cursor import DictCursor
cursor = connect(s3_staging_dir="s3://YOUR_S3_BUCKET/path/to/",
region_name="us-west-2").cursor(cursor=DictCursor, dict_type=OrderedDict)
AsynchronousCursor
~~~~~~~~~~~~~~~~~~
AsynchronousCursor is a simple implementation using the concurrent.futures package.
This cursor does not follow the `DB API 2.0 (PEP 249)`_.
You can use the AsynchronousCursor by specifying the ``cursor_class``
with the connect method or connection object.
.. code:: python
from pyathena import connect
from pyathena.async_cursor import AsyncCursor
cursor = connect(s3_staging_dir="s3://YOUR_S3_BUCKET/path/to/",
region_name="us-west-2",
cursor_class=AsyncCursor).cursor()
.. code:: python
from pyathena.connection import Connection
from pyathena.async_cursor import AsyncCursor
cursor = Connection(s3_staging_dir="s3://YOUR_S3_BUCKET/path/to/",
region_name="us-west-2",
cursor_class=AsyncCursor).cursor()
It can also be used by specifying the cursor class when calling the connection object's cursor method.
.. code:: python
from pyathena import connect
from pyathena.async_cursor import AsyncCursor
cursor = connect(s3_staging_dir="s3://YOUR_S3_BUCKET/path/to/",
region_name="us-west-2").cursor(AsyncCursor)
.. code:: python
from pyathena.connection import Connection
from pyathena.async_cursor import AsyncCursor
cursor = Connection(s3_staging_dir="s3://YOUR_S3_BUCKET/path/to/",
region_name="us-west-2").cursor(AsyncCursor)
The default number of workers is 5 or cpu number * 5.
If you want to change the number of workers you can specify like the following.
.. code:: python
from pyathena import connect
from pyathena.async_cursor import AsyncCursor
cursor = connect(s3_staging_dir="s3://YOUR_S3_BUCKET/path/to/",
region_name="us-west-2",
cursor_class=AsyncCursor).cursor(max_workers=10)
The execute method of the AsynchronousCursor returns the tuple of the query ID and the `future object`_.
.. code:: python
from pyathena import connect
from pyathena.async_cursor import AsyncCursor
cursor = connect(s3_staging_dir="s3://YOUR_S3_BUCKET/path/to/",
region_name="us-west-2",
cursor_class=AsyncCursor).cursor()
query_id, future = cursor.execute("SELECT * FROM many_rows")
The return value of the `future object`_ is an ``AthenaResultSet`` object.
This object has an interface that can fetch and iterate query results similar to synchronous cursors.
It also has information on the result of query execution.
.. code:: python
from pyathena import connect
from pyathena.async_cursor import AsyncCursor
cursor = connect(s3_staging_dir="s3://YOUR_S3_BUCKET/path/to/",
region_name="us-west-2",
cursor_class=AsyncCursor).cursor()
query_id, future = cursor.execute("SELECT * FROM many_rows")
result_set = future.result()
print(result_set.state)
print(result_set.state_change_reason)
print(result_set.completion_date_time)
print(result_set.submission_date_time)
print(result_set.data_scanned_in_bytes)
print(result_set.engine_execution_time_in_millis)
print(result_set.query_queue_time_in_millis)
print(result_set.total_time_in_millis)
print(result_set.query_planning_time_in_millis)
print(result_set.service_processing_time_in_millis)
print(result_set.output_location)
print(result_set.description)
for row in result_set:
print(row)
.. code:: python
from pyathena import connect
from pyathena.async_cursor import AsyncCursor
cursor = connect(s3_staging_dir="s3://YOUR_S3_BUCKET/path/to/",
region_name="us-west-2",
cursor_class=AsyncCursor).cursor()
query_id, future = cursor.execute("SELECT * FROM many_rows")
result_set = future.result()
print(result_set.fetchall())
A query ID is required to cancel a query with the AsynchronousCursor.
.. code:: python
from pyathena import connect
from pyathena.async_cursor import AsyncCursor
cursor = connect(s3_staging_dir="s3://YOUR_S3_BUCKET/path/to/",
region_name="us-west-2",
cursor_class=AsyncCursor).cursor()
query_id, future = cursor.execute("SELECT * FROM many_rows")
cursor.cancel(query_id)
NOTE: The cancel method of the `future object`_ does not cancel the query.
.. _`future object`: https://docs.python.org/3/library/concurrent.futures.html#future-objects
AsynchronousDictCursor
AsyncDIctCursor is an AsyncCursor that can retrieve the query execution result as a dictionary type with column names and values.
You can use the DictCursor by specifying the cursor_class
with the connect method or connection object.
.. code:: python
from pyathena import connect
from pyathena.async_cursor import AsyncDictCursor
cursor = connect(s3_staging_dir="s3://YOUR_S3_BUCKET/path/to/",
region_name="us-west-2",
cursor_class=AsyncDictCursor).cursor()
.. code:: python
from pyathena.connection import Connection
from pyathena.async_cursor import AsyncDictCursor
cursor = Connection(s3_staging_dir="s3://YOUR_S3_BUCKET/path/to/",
region_name="us-west-2",
cursor_class=AsyncDictCursor).cursor()
It can also be used by specifying the cursor class when calling the connection object's cursor method.
.. code:: python
from pyathena import connect
from pyathena.async_cursor import AsyncDictCursor
cursor = connect(s3_staging_dir="s3://YOUR_S3_BUCKET/path/to/",
region_name="us-west-2").cursor(AsyncDictCursor)
.. code:: python
from pyathena.connection import Connection
from pyathena.async_cursor import AsyncDictCursor
cursor = Connection(s3_staging_dir="s3://YOUR_S3_BUCKET/path/to/",
region_name="us-west-2").cursor(AsyncDictCursor)
The basic usage is the same as the AsyncCursor.
.. code:: python
from pyathena.connection import Connection
from pyathena.cursor import DictCursor
cursor = Connection(s3_staging_dir="s3://YOUR_S3_BUCKET/path/to/",
region_name="us-west-2").cursor(AsyncDictCursor)
query_id, future = cursor.execute("SELECT * FROM many_rows LIMIT 10")
result_set = future.result()
for row in result_set:
print(row["a"])
If you want to change the dictionary type (e.g., use OrderedDict), you can specify like the following.
.. code:: python
from collections import OrderedDict
from pyathena import connect
from pyathena.async_cursor import AsyncDictCursor
cursor = connect(s3_staging_dir="s3://YOUR_S3_BUCKET/path/to/",
region_name="us-west-2",
cursor_class=AsyncDictCursor).cursor(dict_type=OrderedDict)
.. code:: python
from collections import OrderedDict
from pyathena import connect
from pyathena.async_cursor import AsyncDictCursor
cursor = connect(s3_staging_dir="s3://YOUR_S3_BUCKET/path/to/",
region_name="us-west-2").cursor(cursor=AsyncDictCursor, dict_type=OrderedDict)
PandasCursor
PandasCursor directly handles the CSV file of the query execution result output to S3.
This cursor is to download the CSV file after executing the query, and then loaded into `DataFrame object`_.
Performance is better than fetching data with Cursor.
You can use the PandasCursor by specifying the ``cursor_class``
with the connect method or connection object.
.. code:: python
from pyathena import connect
from pyathena.pandas.cursor import PandasCursor
cursor = connect(s3_staging_dir="s3://YOUR_S3_BUCKET/path/to/",
region_name="us-west-2",
cursor_class=PandasCursor).cursor()
.. code:: python
from pyathena.connection import Connection
from pyathena.pandas.cursor import PandasCursor
cursor = Connection(s3_staging_dir="s3://YOUR_S3_BUCKET/path/to/",
region_name="us-west-2",
cursor_class=PandasCursor).cursor()
It can also be used by specifying the cursor class when calling the connection object's cursor method.
.. code:: python
from pyathena import connect
from pyathena.pandas.cursor import PandasCursor
cursor = connect(s3_staging_dir="s3://YOUR_S3_BUCKET/path/to/",
region_name="us-west-2").cursor(PandasCursor)
.. code:: python
from pyathena.connection import Connection
from pyathena.pandas.cursor import PandasCursor
cursor = Connection(s3_staging_dir="s3://YOUR_S3_BUCKET/path/to/",
region_name="us-west-2").cursor(PandasCursor)
The as_pandas method returns a `DataFrame object`_.
.. code:: python
from pyathena import connect
from pyathena.pandas.cursor import PandasCursor
cursor = connect(s3_staging_dir="s3://YOUR_S3_BUCKET/path/to/",
region_name="us-west-2",
cursor_class=PandasCursor).cursor()
df = cursor.execute("SELECT * FROM many_rows").as_pandas()
print(df.describe())
print(df.head())
Support fetch and iterate query results.
.. code:: python
from pyathena import connect
from pyathena.pandas.cursor import PandasCursor
cursor = connect(s3_staging_dir="s3://YOUR_S3_BUCKET/path/to/",
region_name="us-west-2",
cursor_class=PandasCursor).cursor()
cursor.execute("SELECT * FROM many_rows")
print(cursor.fetchone())
print(cursor.fetchmany())
print(cursor.fetchall())
.. code:: python
from pyathena import connect
from pyathena.pandas.cursor import PandasCursor
cursor = connect(s3_staging_dir="s3://YOUR_S3_BUCKET/path/to/",
region_name="us-west-2",
cursor_class=PandasCursor).cursor()
cursor.execute("SELECT * FROM many_rows")
for row in cursor:
print(row)
The DATE and TIMESTAMP of Athena's data type are returned as `pandas.Timestamp`_ type.
.. code:: python
from pyathena import connect
from pyathena.pandas.cursor import PandasCursor
cursor = connect(s3_staging_dir="s3://YOUR_S3_BUCKET/path/to/",
region_name="us-west-2",
cursor_class=PandasCursor).cursor()
cursor.execute("SELECT col_timestamp FROM one_row_complex")
print(type(cursor.fetchone()[0])) # <class 'pandas._libs.tslibs.timestamps.Timestamp'>
Execution information of the query can also be retrieved.
.. code:: python
from pyathena import connect
from pyathena.pandas.cursor import PandasCursor
cursor = connect(s3_staging_dir="s3://YOUR_S3_BUCKET/path/to/",
region_name="us-west-2",
cursor_class=PandasCursor).cursor()
cursor.execute("SELECT * FROM many_rows")
print(cursor.state)
print(cursor.state_change_reason)
print(cursor.completion_date_time)
print(cursor.submission_date_time)
print(cursor.data_scanned_in_bytes)
print(cursor.engine_execution_time_in_millis)
print(cursor.query_queue_time_in_millis)
print(cursor.total_time_in_millis)
print(cursor.query_planning_time_in_millis)
print(cursor.service_processing_time_in_millis)
print(cursor.output_location)
If you want to customize the Dataframe object dtypes and converters, create a converter class like this:
.. code:: python
from pyathena.converter import Converter
class CustomPandasTypeConverter(Converter):
def __init__(self):
super(CustomPandasTypeConverter, self).__init__(
mappings=None,
types={
"boolean": object,
"tinyint": float,
"smallint": float,
"integer": float,
"bigint": float,
"float": float,
"real": float,
"double": float,
"decimal": float,
"char": str,
"varchar": str,
"array": str,
"map": str,
"row": str,
"varbinary": str,
"json": str,
}
)
def convert(self, type_, value):
# Not used in PandasCursor.
pass
Specify the combination of converter functions in the mappings argument and the dtypes combination in the types argument.
Then you simply specify an instance of this class in the convertes argument when creating a connection or cursor.
.. code:: python
from pyathena import connect
from pyathena.pandas.cursor import PandasCursor
cursor = connect(s3_staging_dir="s3://YOUR_S3_BUCKET/path/to/",
region_name="us-west-2").cursor(PandasCursor, converter=CustomPandasTypeConverter())
.. code:: python
from pyathena import connect
from pyathena.pandas.cursor import PandasCursor
cursor = connect(s3_staging_dir="s3://YOUR_S3_BUCKET/path/to/",
region_name="us-west-2",
converter=CustomPandasTypeConverter()).cursor(PandasCursor)
If you want to change the NaN behavior of Pandas Dataframe,
you can do so by using the ``keep_default_na``, ``na_values`` and ``quoting`` arguments of the cursor object's execute method.
.. code:: python
from pyathena import connect
from pyathena.pandas.cursor import PandasCursor
cursor = connect(s3_staging_dir="s3://YOUR_S3_BUCKET/path/to/",
region_name="us-west-2",
cursor_class=PandasCursor).cursor()
df = cursor.execute("SELECT * FROM many_rows",
keep_default_na=False,
na_values=[""]).as_pandas()
NOTE: PandasCursor handles the CSV file on memory. Pay attention to the memory capacity.
.. _`DataFrame object`: https://pandas.pydata.org/pandas-docs/stable/reference/api/pandas.DataFrame.html
.. _`pandas.Timestamp`: https://pandas.pydata.org/pandas-docs/stable/reference/api/pandas.Timestamp.html
AsyncPandasCursor
AsyncPandasCursor is an AsyncCursor that can handle Pandas DataFrame. This cursor directly handles the CSV of query results output to S3 in the same way as PandasCursor.
You can use the AsyncPandasCursor by specifying the cursor_class
with the connect method or connection object.
.. code:: python
from pyathena import connect
from pyathena.pandas.async_cursor import AsyncPandasCursor
cursor = connect(s3_staging_dir="s3://YOUR_S3_BUCKET/path/to/",
region_name="us-west-2",
cursor_class=AsyncPandasCursor).cursor()
.. code:: python
from pyathena.connection import Connection
from pyathena.pandas.async_cursor import AsyncPandasCursor
cursor = Connection(s3_staging_dir="s3://YOUR_S3_BUCKET/path/to/",
region_name="us-west-2",
cursor_class=AsyncPandasCursor).cursor()
It can also be used by specifying the cursor class when calling the connection object's cursor method.
.. code:: python
from pyathena import connect
from pyathena.pandas.async_cursor import AsyncPandasCursor
cursor = connect(s3_staging_dir="s3://YOUR_S3_BUCKET/path/to/",
region_name="us-west-2").cursor(AsyncPandasCursor)
.. code:: python
from pyathena.connection import Connection
from pyathena.pandas.async_cursor import AsyncPandasCursor
cursor = Connection(s3_staging_dir="s3://YOUR_S3_BUCKET/path/to/",
region_name="us-west-2").cursor(AsyncPandasCursor)
The default number of workers is 5 or cpu number * 5. If you want to change the number of workers you can specify like the following.
.. code:: python
from pyathena import connect
from pyathena.pandas.async_cursor import AsyncPandasCursor
cursor = connect(s3_staging_dir="s3://YOUR_S3_BUCKET/path/to/",
region_name="us-west-2",
cursor_class=AsyncPandasCursor).cursor(max_workers=10)
The execute method of the AsynchronousPandasCursor returns the tuple of the query ID and the future object
_.
.. code:: python
from pyathena import connect
from pyathena.pandas.async_cursor import AsyncPandasCursor
cursor = connect(s3_staging_dir="s3://YOUR_S3_BUCKET/path/to/",
region_name="us-west-2",
cursor_class=AsyncPandasCursor).cursor()
query_id, future = cursor.execute("SELECT * FROM many_rows")
The return value of the future object
_ is an AthenaPandasResultSet
object.
This object has an interface similar to AthenaResultSetObject
.
.. code:: python
from pyathena import connect
from pyathena.pandas.async_cursor import AsyncPandasCursor
cursor = connect(s3_staging_dir="s3://YOUR_S3_BUCKET/path/to/",
region_name="us-west-2",
cursor_class=AsyncPandasCursor).cursor()
query_id, future = cursor.execute("SELECT * FROM many_rows")
result_set = future.result()
print(result_set.state)
print(result_set.state_change_reason)
print(result_set.completion_date_time)
print(result_set.submission_date_time)
print(result_set.data_scanned_in_bytes)
print(result_set.engine_execution_time_in_millis)
print(result_set.query_queue_time_in_millis)
print(result_set.total_time_in_millis)
print(result_set.query_planning_time_in_millis)
print(result_set.service_processing_time_in_millis)
print(result_set.output_location)
print(result_set.description)
for row in result_set:
print(row)
.. code:: python
from pyathena import connect
from pyathena.pandas.async_cursor import AsyncPandasCursor
cursor = connect(s3_staging_dir="s3://YOUR_S3_BUCKET/path/to/",
region_name="us-west-2",
cursor_class=AsyncPandasCursor).cursor()
query_id, future = cursor.execute("SELECT * FROM many_rows")
result_set = future.result()
print(result_set.fetchall())
This object also has an as_pandas method that returns a DataFrame object
_ similar to the PandasCursor.
.. code:: python
from pyathena import connect
from pyathena.pandas.async_cursor import AsyncPandasCursor
cursor = connect(s3_staging_dir="s3://YOUR_S3_BUCKET/path/to/",
region_name="us-west-2",
cursor_class=AsyncPandasCursor).cursor()
query_id, future = cursor.execute("SELECT * FROM many_rows")
result_set = future.result()
df = result_set.as_pandas()
print(df.describe())
print(df.head())
The DATE and TIMESTAMP of Athena's data type are returned as pandas.Timestamp
_ type.
.. code:: python
from pyathena import connect
from pyathena.pandas.async_cursor import AsyncPandasCursor
cursor = connect(s3_staging_dir="s3://YOUR_S3_BUCKET/path/to/",
region_name="us-west-2",
cursor_class=AsyncPandasCursor).cursor()
query_id, future = cursor.execute("SELECT col_timestamp FROM one_row_complex")
result_set = future.result()
print(type(result_set.fetchone()[0])) # <class 'pandas._libs.tslibs.timestamps.Timestamp'>
As with AsynchronousCursor, you need a query ID to cancel a query.
.. code:: python
from pyathena import connect
from pyathena.pandas.async_cursor import AsyncPandasCursor
cursor = connect(s3_staging_dir="s3://YOUR_S3_BUCKET/path/to/",
region_name="us-west-2",
cursor_class=AsyncPandasCursor).cursor()
query_id, future = cursor.execute("SELECT * FROM many_rows")
cursor.cancel(query_id)
Quickly re-run queries
You can attempt to re-use the results from a previously executed query to help save time and money in the cases where your underlying data isn't changing.
Set the ``cache_size`` or ``cache_expiration_time`` parameter of ``cursor.execute()`` to a number larger than 0 to enable caching.
.. code:: python
from pyathena import connect
cursor = connect(s3_staging_dir="s3://YOUR_S3_BUCKET/path/to/",
region_name="us-west-2").cursor()
cursor.execute("SELECT * FROM one_row") # run once
print(cursor.query_id)
cursor.execute("SELECT * FROM one_row", cache_size=10) # re-use earlier results
print(cursor.query_id) # You should expect to see the same Query ID
The unit of ``expiration_time`` is seconds. To use the results of queries executed up to one hour ago, specify like the following.
.. code:: python
from pyathena import connect
cursor = connect(s3_staging_dir="s3://YOUR_S3_BUCKET/path/to/",
region_name="us-west-2").cursor()
cursor.execute("SELECT * FROM one_row", cache_expiration_time=3600) # Use queries executed within 1 hour as cache.
If ``cache_size`` is not specified, the value of ``sys.maxsize`` will be automatically set and all query results executed up to one hour ago will be checked.
Therefore, it is recommended to specify ``cache_expiration_time`` together with ``cache_size`` like the following.
.. code:: python
from pyathena import connect
cursor = connect(s3_staging_dir="s3://YOUR_S3_BUCKET/path/to/",
region_name="us-west-2").cursor()
cursor.execute("SELECT * FROM one_row", cache_size=100, cache_expiration_time=3600) # Use the last 100 queries within 1 hour as cache.
Results will only be re-used if the query strings match *exactly*,
and the query was a DML statement (the assumption being that you always want to re-run queries like ``CREATE TABLE`` and ``DROP TABLE``).
The S3 staging directory is not checked, so it's possible that the location of the results is not in your provided ``s3_staging_dir``.
Credentials
-----------
Support `Boto3 credentials`_.
.. _`Boto3 credentials`: http://boto3.readthedocs.io/en/latest/guide/configuration.html
Additional environment variable:
.. code:: bash
$ export AWS_ATHENA_S3_STAGING_DIR=s3://YOUR_S3_BUCKET/path/to/
$ export AWS_ATHENA_WORK_GROUP=YOUR_WORK_GROUP
Examples
~~~~~~~~
Passing credentials as parameters
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
.. code:: python
from pyathena import connect
cursor = connect(aws_access_key_id="YOUR_ACCESS_KEY_ID",
aws_secret_access_key="YOUR_SECRET_ACCESS_KEY",
s3_staging_dir="s3://YOUR_S3_BUCKET/path/to/",
region_name="us-west-2").cursor()
.. code:: python
from pyathena import connect
cursor = connect(aws_access_key_id="YOUR_ACCESS_KEY_ID",
aws_secret_access_key="YOUR_SECRET_ACCESS_KEY",
aws_session_token="YOUR_SESSION_TOKEN",
s3_staging_dir="s3://YOUR_S3_BUCKET/path/to/",
region_name="us-west-2").cursor()
Multi-factor authentication
^^^^^^^^^^^^^^^^^^^^^^^^^^^
You will be prompted to enter the MFA code.
The program execution will be blocked until the MFA code is entered.
.. code:: python
from pyathena import connect
cursor = connect(duration_seconds=3600,
serial_number="arn:aws:iam::ACCOUNT_NUMBER_WITHOUT_HYPHENS:mfa/MFA_DEVICE_ID",
s3_staging_dir="s3://YOUR_S3_BUCKET/path/to/",
region_name="us-west-2").cursor()
Shared credentials file
^^^^^^^^^^^^^^^^^^^^^^^
The shared credentials file has a default location of ~/.aws/credentials.
If you use the default profile, there is no need to specify credential information.
.. code:: python
from pyathena import connect
cursor = connect(s3_staging_dir="s3://YOUR_S3_BUCKET/path/to/",
region_name="us-west-2").cursor()
You can also specify a profile other than the default.
.. code:: python
from pyathena import connect
cursor = connect(profile_name="YOUR_PROFILE_NAME",
s3_staging_dir="s3://YOUR_S3_BUCKET/path/to/",
region_name="us-west-2").cursor()
Assume role provider
^^^^^^^^^^^^^^^^^^^^
.. code:: python
from pyathena import connect
cursor = connect(role_arn="YOUR_ASSUME_ROLE_ARN",
role_session_name="PyAthena-session",
duration_seconds=3600,
s3_staging_dir="s3://YOUR_S3_BUCKET/path/to/",
region_name="us-west-2").cursor()
Assume role provider with MFA
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
You will be prompted to enter the MFA code.
The program execution will be blocked until the MFA code is entered.
.. code:: python
from pyathena import connect
cursor = connect(role_arn="YOUR_ASSUME_ROLE_ARN",
role_session_name="PyAthena-session",
duration_seconds=3600,
serial_number="arn:aws:iam::ACCOUNT_NUMBER_WITHOUT_HYPHENS:mfa/MFA_DEVICE_ID",
s3_staging_dir="s3://YOUR_S3_BUCKET/path/to/",
region_name="us-west-2").cursor()
Instance profiles
^^^^^^^^^^^^^^^^^
No need to specify credential information.
.. code:: python
from pyathena import connect
cursor = connect(s3_staging_dir="s3://YOUR_S3_BUCKET/path/to/",
region_name="us-west-2").cursor()
Testing
-------
Depends on the following environment variables:
.. code:: bash
$ export AWS_ACCESS_KEY_ID=YOUR_ACCESS_KEY_ID
$ export AWS_SECRET_ACCESS_KEY=YOUR_SECRET_ACCESS_KEY
$ export AWS_DEFAULT_REGION=us-west-2
$ export AWS_ATHENA_S3_STAGING_DIR=s3://YOUR_S3_BUCKET/path/to/
And you need to create a workgroup named ``test-pyathena`` with the ``Query result location`` configuration.
Run test
~~~~~~~~
.. code:: bash
$ pip install poetry
$ poetry install -v
$ poetry run scripts/test_data/upload_test_data.sh
$ poetry run pytest
$ poetry run scripts/test_data/delete_test_data.sh
Run test multiple Python versions
.. code:: bash
$ pip install poetry
$ poetry install -v
$ poetry run scripts/test_data/upload_test_data.sh
$ pyenv local 3.9.1 3.8.2 3.7.2 3.6.8
$ poetry run tox
$ poetry run scripts/test_data/delete_test_data.sh
Code formatting
The code formatting uses black
_ and isort
_.
Appy format
.. code:: bash
$ make fmt
Check format
.. code:: bash
$ make chk
.. _black
: https://github.com/psf/black
.. _isort
: https://github.com/timothycrosley/isort