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步骤 3:创建表、索引与示例数据
重要
终止支持通知:现有客户可以在2025年7月31日终止支持QLDB之前使用亚马逊。有关更多详细信息,请参阅将亚马逊QLDB账本迁移到亚马逊 Aurora Postgr SQL
当您的Amazon QLDB 账本处于活动状态并接受连接时,您可以开始创建有关车辆、车主和注册信息的数据表。创建表和索引后,可以向其中加载数据。
在此步骤中,您将在vehicle-registration
分类账中创建四个表格:
-
VehicleRegistration
-
Vehicle
-
Person
-
DriversLicense
您还可创建以下索引。
表名称 | 字段 |
---|---|
VehicleRegistration |
VIN |
VehicleRegistration |
LicensePlateNumber |
Vehicle |
VIN |
Person |
GovId |
DriversLicense |
LicenseNumber |
DriversLicense |
PersonId |
插入示例数据时,首先要在 Person
表格中插入文档。然后使用系统分配的、来自每个Person
文档的id
填充适当VehicleRegistration
和 DriversLicense
文档中的相应文档。
提示
创建表和索引
-
编译并运行以下程序(
create_table.py
)以创建前面提到的表。注意
该程序演示如何使用
execute_lambda
函数。在此示例中,您使用 lambda 表达式在单个事务中运行多个CREATE TABLE
PartiQL 语句该 方法采用隐式启动事务,运行 lambda 中的所有语句,然后自动提交事务。
-
要运行该程序,请输入以下命令。
python create_table.py
-
如前所述,编译并运行以下程序(
create_index.py
),以在表上创建索引。 -
要运行该程序,请输入以下命令。
python create_index.py
将样本数据加载到 表中
-
查看以下文件(
sample_data.py
),该文件代表您插入vehicle-registration
表中的示例数据。此文件也从amazon.ion
软件包导出,以提供用于转换、解析和打印 Amazon Ion 数据的辅助函数。# Copyright 2019 Amazon.com, Inc. or its affiliates. All Rights Reserved. # SPDX-License-Identifier: MIT-0 # # Permission is hereby granted, free of charge, to any person obtaining a copy of this # software and associated documentation files (the "Software"), to deal in the Software # without restriction, including without limitation the rights to use, copy, modify, # merge, publish, distribute, sublicense, and/or sell copies of the Software, and to # permit persons to whom the Software is furnished to do so. # # THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, # INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A # PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT # HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION # OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE # SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. from datetime import datetime from decimal import Decimal from logging import basicConfig, getLogger, INFO from amazon.ion.simple_types import IonPyBool, IonPyBytes, IonPyDecimal, IonPyDict, IonPyFloat, IonPyInt, IonPyList, \ IonPyNull, IonPySymbol, IonPyText, IonPyTimestamp from amazon.ion.simpleion import dumps, loads logger = getLogger(__name__) basicConfig(level=INFO) IonValue = (IonPyBool, IonPyBytes, IonPyDecimal, IonPyDict, IonPyFloat, IonPyInt, IonPyList, IonPyNull, IonPySymbol, IonPyText, IonPyTimestamp) class SampleData: """ Sample domain objects for use throughout this tutorial. """ DRIVERS_LICENSE = [ { 'PersonId': '', 'LicenseNumber': 'LEWISR261LL', 'LicenseType': 'Learner', 'ValidFromDate': datetime(2016, 12, 20), 'ValidToDate': datetime(2020, 11, 15) }, { 'PersonId': '', 'LicenseNumber': 'LOGANB486CG', 'LicenseType': 'Probationary', 'ValidFromDate': datetime(2016, 4, 6), 'ValidToDate': datetime(2020, 11, 15) }, { 'PersonId': '', 'LicenseNumber': '744 849 301', 'LicenseType': 'Full', 'ValidFromDate': datetime(2017, 12, 6), 'ValidToDate': datetime(2022, 10, 15) }, { 'PersonId': '', 'LicenseNumber': 'P626-168-229-765', 'LicenseType': 'Learner', 'ValidFromDate': datetime(2017, 8, 16), 'ValidToDate': datetime(2021, 11, 15) }, { 'PersonId': '', 'LicenseNumber': 'S152-780-97-415-0', 'LicenseType': 'Probationary', 'ValidFromDate': datetime(2015, 8, 15), 'ValidToDate': datetime(2021, 8, 21) } ] PERSON = [ { 'FirstName': 'Raul', 'LastName': 'Lewis', 'Address': '1719 University Street, Seattle, WA, 98109', 'DOB': datetime(1963, 8, 19), 'GovId': 'LEWISR261LL', 'GovIdType': 'Driver License' }, { 'FirstName': 'Brent', 'LastName': 'Logan', 'DOB': datetime(1967, 7, 3), 'Address': '43 Stockert Hollow Road, Everett, WA, 98203', 'GovId': 'LOGANB486CG', 'GovIdType': 'Driver License' }, { 'FirstName': 'Alexis', 'LastName': 'Pena', 'DOB': datetime(1974, 2, 10), 'Address': '4058 Melrose Street, Spokane Valley, WA, 99206', 'GovId': '744 849 301', 'GovIdType': 'SSN' }, { 'FirstName': 'Melvin', 'LastName': 'Parker', 'DOB': datetime(1976, 5, 22), 'Address': '4362 Ryder Avenue, Seattle, WA, 98101', 'GovId': 'P626-168-229-765', 'GovIdType': 'Passport' }, { 'FirstName': 'Salvatore', 'LastName': 'Spencer', 'DOB': datetime(1997, 11, 15), 'Address': '4450 Honeysuckle Lane, Seattle, WA, 98101', 'GovId': 'S152-780-97-415-0', 'GovIdType': 'Passport' } ] VEHICLE = [ { 'VIN': '1N4AL11D75C109151', 'Type': 'Sedan', 'Year': 2011, 'Make': 'Audi', 'Model': 'A5', 'Color': 'Silver' }, { 'VIN': 'KM8SRDHF6EU074761', 'Type': 'Sedan', 'Year': 2015, 'Make': 'Tesla', 'Model': 'Model S', 'Color': 'Blue' }, { 'VIN': '3HGGK5G53FM761765', 'Type': 'Motorcycle', 'Year': 2011, 'Make': 'Ducati', 'Model': 'Monster 1200', 'Color': 'Yellow' }, { 'VIN': '1HVBBAANXWH544237', 'Type': 'Semi', 'Year': 2009, 'Make': 'Ford', 'Model': 'F 150', 'Color': 'Black' }, { 'VIN': '1C4RJFAG0FC625797', 'Type': 'Sedan', 'Year': 2019, 'Make': 'Mercedes', 'Model': 'CLK 350', 'Color': 'White' } ] VEHICLE_REGISTRATION = [ { 'VIN': '1N4AL11D75C109151', 'LicensePlateNumber': 'LEWISR261LL', 'State': 'WA', 'City': 'Seattle', 'ValidFromDate': datetime(2017, 8, 21), 'ValidToDate': datetime(2020, 5, 11), 'PendingPenaltyTicketAmount': Decimal('90.25'), 'Owners': { 'PrimaryOwner': {'PersonId': ''}, 'SecondaryOwners': [] } }, { 'VIN': 'KM8SRDHF6EU074761', 'LicensePlateNumber': 'CA762X', 'State': 'WA', 'City': 'Kent', 'PendingPenaltyTicketAmount': Decimal('130.75'), 'ValidFromDate': datetime(2017, 9, 14), 'ValidToDate': datetime(2020, 6, 25), 'Owners': { 'PrimaryOwner': {'PersonId': ''}, 'SecondaryOwners': [] } }, { 'VIN': '3HGGK5G53FM761765', 'LicensePlateNumber': 'CD820Z', 'State': 'WA', 'City': 'Everett', 'PendingPenaltyTicketAmount': Decimal('442.30'), 'ValidFromDate': datetime(2011, 3, 17), 'ValidToDate': datetime(2021, 3, 24), 'Owners': { 'PrimaryOwner': {'PersonId': ''}, 'SecondaryOwners': [] } }, { 'VIN': '1HVBBAANXWH544237', 'LicensePlateNumber': 'LS477D', 'State': 'WA', 'City': 'Tacoma', 'PendingPenaltyTicketAmount': Decimal('42.20'), 'ValidFromDate': datetime(2011, 10, 26), 'ValidToDate': datetime(2023, 9, 25), 'Owners': { 'PrimaryOwner': {'PersonId': ''}, 'SecondaryOwners': [] } }, { 'VIN': '1C4RJFAG0FC625797', 'LicensePlateNumber': 'TH393F', 'State': 'WA', 'City': 'Olympia', 'PendingPenaltyTicketAmount': Decimal('30.45'), 'ValidFromDate': datetime(2013, 9, 2), 'ValidToDate': datetime(2024, 3, 19), 'Owners': { 'PrimaryOwner': {'PersonId': ''}, 'SecondaryOwners': [] } } ] def convert_object_to_ion(py_object): """ Convert a Python object into an Ion object. :type py_object: object :param py_object: The object to convert. :rtype: :py:class:`amazon.ion.simple_types.IonPyValue` :return: The converted Ion object. """ ion_object = loads(dumps(py_object)) return ion_object def to_ion_struct(key, value): """ Convert the given key and value into an Ion struct. :type key: str :param key: The key which serves as an unique identifier. :type value: str :param value: The value associated with a given key. :rtype: :py:class:`amazon.ion.simple_types.IonPyDict` :return: The Ion dictionary object. """ ion_struct = dict() ion_struct[key] = value return loads(str(ion_struct)) def get_document_ids(transaction_executor, table_name, field, value): """ Gets the document IDs from the given table. :type transaction_executor: :py:class:`pyqldb.execution.executor.Executor` :param transaction_executor: An Executor object allowing for execution of statements within a transaction. :type table_name: str :param table_name: The table name to query. :type field: str :param field: A field to query. :type value: str :param value: The key of the given field. :rtype: list :return: A list of document IDs. """ query = "SELECT id FROM {} AS t BY id WHERE t.{} = ?".format(table_name, field) cursor = transaction_executor.execute_statement(query, convert_object_to_ion(value)) return list(map(lambda table: table.get('id'), cursor)) def get_document_ids_from_dml_results(result): """ Return a list of modified document IDs as strings from DML results. :type result: :py:class:`pyqldb.cursor.buffered_cursor.BufferedCursor` :param: result: The result set from DML operation. :rtype: list :return: List of document IDs. """ ret_val = list(map(lambda x: x.get('documentId'), result)) return ret_val def print_result(cursor): """ Pretty print the result set. Returns the number of documents in the result set. :type cursor: :py:class:`pyqldb.cursor.stream_cursor.StreamCursor`/ :py:class:`pyqldb.cursor.buffered_cursor.BufferedCursor` :param cursor: An instance of the StreamCursor or BufferedCursor class. :rtype: int :return: Number of documents in the result set. """ result_counter = 0 for row in cursor: # Each row would be in Ion format. print_ion(row) result_counter += 1 return result_counter def print_ion(ion_value): """ Pretty print an Ion Value. :type ion_value: :py:class:`amazon.ion.simple_types.IonPySymbol` :param ion_value: Any Ion Value to be pretty printed. """ logger.info(dumps(ion_value, binary=False, indent=' ', omit_version_marker=True))
注意
该
get_document_ids
函数运行一个查询,IDs从表中返回系统分配的文档。要了解更多信息,请参阅通过 BY 子句查询文档 ID。 -
使用以下程序(
insert_document.py
),将示例数据插入表内。注意
-
该程序演示如何使用参数化值调用
execute_statement
方法。除了要运行的 PartiQL 语句之外,您还可以传递数据参数。在语句字符串中将问号(?
)作为变量占位符。 -
如果
INSERT
语句成功,则返回每个插入文档的id
。
-
-
要运行该程序,请输入以下命令。
python insert_document.py
接下来,您可以使用 SELECT
语句从 vehicle-registration
分类账中的表中读取数据。继续执行步骤 4:查询分类账中的表。