Spark SQL 进行交互。类似于 SQL 数据库代理，它旨在处理关于 Spark SQL 的一般查询并促进错误恢复。
注意：请注意，由于此代理正在积极开发中，所有答案可能并不正确。此外，不能保证代理在给定某些问题时不会在您的 Spark 集群上执行 DML 语句。在敏感数据上运行时请务必小心！
初始化
from langchain_community.agent_toolkits import SparkSQLToolkit, create_spark_sql_agent
from langchain_community.utilities.spark_sql import SparkSQL
from langchain_openai import ChatOpenAI
from pyspark.sql import SparkSession
spark = SparkSession.builder.getOrCreate()
schema = "langchain_example"
spark.sql(f"CREATE DATABASE IF NOT EXISTS {schema}")
spark.sql(f"USE {schema}")
csv_file_path = "titanic.csv"
table = "titanic"
spark.read.csv(csv_file_path, header=True, inferSchema=True).write.saveAsTable(table)
spark.table(table).show()
Setting default log level to "WARN".
To adjust logging level use sc.setLogLevel(newLevel). For SparkR, use setLogLevel(newLevel).
23/05/18 16:03:10 WARN NativeCodeLoader: Unable to load native-hadoop library for your platform... using built-in Java classes where applicable
+-----------+--------+------+--------------------+------+----+-----+-----+----------------+-------+-----+--------+
|PassengerId|Survived|Pclass| Name| Sex| Age|SibSp|Parch| Ticket| Fare|Cabin|Embarked|
+-----------+--------+------+--------------------+------+----+-----+-----+----------------+-------+-----+--------+
| 1| 0| 3|Braund, Mr. Owen ...| male|22.0| 1| 0| A/5 21171| 7.25| null| S|
| 2| 1| 1|Cumings, Mrs. Joh...|female|38.0| 1| 0| PC 17599|71.2833| C85| C|
| 3| 1| 3|Heikkinen, Miss. ...|female|26.0| 0| 0|STON/O2. 3101282| 7.925| null| S|
| 4| 1| 1|Futrelle, Mrs. Ja...|female|35.0| 1| 0| 113803| 53.1| C123| S|
| 5| 0| 3|Allen, Mr. Willia...| male|35.0| 0| 0| 373450| 8.05| null| S|
| 6| 0| 3| Moran, Mr. James| male|null| 0| 0| 330877| 8.4583| null| Q|
| 7| 0| 1|McCarthy, Mr. Tim...| male|54.0| 0| 0| 17463|51.8625| E46| S|
| 8| 0| 3|Palsson, Master. ...| male| 2.0| 3| 1| 349909| 21.075| null| S|
| 9| 1| 3|Johnson, Mrs. Osc...|female|27.0| 0| 2| 347742|11.1333| null| S|
| 10| 1| 2|Nasser, Mrs. Nich...|female|14.0| 1| 0| 237736|30.0708| null| C|
| 11| 1| 3|Sandstrom, Miss. ...|female| 4.0| 1| 1| PP 9549| 16.7| G6| S|
| 12| 1| 1|Bonnell, Miss. El...|female|58.0| 0| 0| 113783| 26.55| C103| S|
| 13| 0| 3|Saundercock, Mr. ...| male|20.0| 0| 0| A/5. 2151| 8.05| null| S|
| 14| 0| 3|Andersson, Mr. An...| male|39.0| 1| 5| 347082| 31.275| null| S|
| 15| 0| 3|Vestrom, Miss. Hu...|female|14.0| 0| 0| 350406| 7.8542| null| S|
| 16| 1| 2|Hewlett, Mrs. (Ma...|female|55.0| 0| 0| 248706| 16.0| null| S|
| 17| 0| 3|Rice, Master. Eugene| male| 2.0| 4| 1| 382652| 29.125| null| Q|
| 18| 1| 2|Williams, Mr. Cha...| male|null| 0| 0| 244373| 13.0| null| S|
| 19| 0| 3|Vander Planke, Mr...|female|31.0| 1| 0| 345763| 18.0| null| S|
| 20| 1| 3|Masselmani, Mrs. ...|female|null| 0| 0| 2649| 7.225| null| C|
+-----------+--------+------+--------------------+------+----+-----+-----+----------------+-------+-----+--------+
only showing top 20 rows
# 注意，您也可以通过 Spark connect 连接到 Spark。例如：
# db = SparkSQL.from_uri("sc://localhost:15002", schema=schema)
spark_sql = SparkSQL(schema=schema)
llm = ChatOpenAI(temperature=0)
toolkit = SparkSQLToolkit(db=spark_sql, llm=llm)
agent_executor = create_spark_sql_agent(llm=llm, toolkit=toolkit, verbose=True)
示例：描述表
agent_executor.run("Describe the titanic table")
> Entering new AgentExecutor chain...
Action: list_tables_sql_db
Action Input:
Observation: titanic
Thought:I found the titanic table. Now I need to get the schema and sample rows for the titanic table.
Action: schema_sql_db
Action Input: titanic
Observation: CREATE TABLE langchain_example.titanic (
PassengerId INT,
Survived INT,
Pclass INT,
Name STRING,
Sex STRING,
Age DOUBLE,
SibSp INT,
Parch INT,
Ticket STRING,
Fare DOUBLE,
Cabin STRING,
Embarked STRING)
;
/*
3 rows from titanic table:
PassengerId Survived Pclass Name Sex Age SibSp Parch Ticket Fare Cabin Embarked
1 0 3 Braund, Mr. Owen Harris male 22.0 1 0 A/5 21171 7.25 None S
2 1 1 Cumings, Mrs. John Bradley (Florence Briggs Thayer) female 38.0 1 0 PC 17599 71.2833 C85 C
3 1 3 Heikkinen, Miss. Laina female 26.0 0 0 STON/O2. 3101282 7.925 None S
*/
Thought:I now know the schema and sample rows for the titanic table.
Final Answer: The titanic table has the following columns: PassengerId (INT), Survived (INT), Pclass (INT), Name (STRING), Sex (STRING), Age (DOUBLE), SibSp (INT), Parch (INT), Ticket (STRING), Fare (DOUBLE), Cabin (STRING), and Embarked (STRING). Here are some sample rows from the table:
1. PassengerId: 1, Survived: 0, Pclass: 3, Name: Braund, Mr. Owen Harris, Sex: male, Age: 22.0, SibSp: 1, Parch: 0, Ticket: A/5 21171, Fare: 7.25, Cabin: None, Embarked: S
2. PassengerId: 2, Survived: 1, Pclass: 1, Name: Cumings, Mrs. John Bradley (Florence Briggs Thayer), Sex: female, Age: 38.0, SibSp: 1, Parch: 0, Ticket: PC 17599, Fare: 71.2833, Cabin: C85, Embarked: C
3. PassengerId: 3, Survived: 1, Pclass: 3, Name: Heikkinen, Miss. Laina, Sex: female, Age: 26.0, SibSp: 0, Parch: 0, Ticket: STON/O2. 3101282, Fare: 7.925, Cabin: None, Embarked: S
> Finished chain.
'The titanic table has the following columns: PassengerId (INT), Survived (INT), Pclass (INT), Name (STRING), Sex (STRING), Age (DOUBLE), SibSp (INT), Parch (INT), Ticket (STRING), Fare (DOUBLE), Cabin (STRING), and Embarked (STRING). Here are some sample rows from the table: \n\n1. PassengerId: 1, Survived: 0, Pclass: 3, Name: Braund, Mr. Owen Harris, Sex: male, Age: 22.0, SibSp: 1, Parch: 0, Ticket: A/5 21171, Fare: 7.25, Cabin: None, Embarked: S\n2. PassengerId: 2, Survived: 1, Pclass: 1, Name: Cumings, Mrs. John Bradley (Florence Briggs Thayer), Sex: female, Age: 38.0, SibSp: 1, Parch: 0, Ticket: PC 17599, Fare: 71.2833, Cabin: C85, Embarked: C\n3. PassengerId: 3, Survived: 1, Pclass: 3, Name: Heikkinen, Miss. Laina, Sex: female, Age: 26.0, SibSp: 0, Parch: 0, Ticket: STON/O2. 3101282, Fare: 7.925, Cabin: None, Embarked: S'
示例：运行查询
agent_executor.run("whats the square root of the average age?")
> Entering new AgentExecutor chain...
Action: list_tables_sql_db
Action Input:
Observation: titanic
Thought:I should check the schema of the titanic table to see if there is an age column.
Action: schema_sql_db
Action Input: titanic
Observation: CREATE TABLE langchain_example.titanic (
PassengerId INT,
Survived INT,
Pclass INT,
Name STRING,
Sex STRING,
Age DOUBLE,
SibSp INT,
Parch INT,
Ticket STRING,
Fare DOUBLE,
Cabin STRING,
Embarked STRING)
;
/*
3 rows from titanic table:
PassengerId Survived Pclass Name Sex Age SibSp Parch Ticket Fare Cabin Embarked
1 0 3 Braund, Mr. Owen Harris male 22.0 1 0 A/5 21171 7.25 None S
2 1 1 Cumings, Mrs. John Bradley (Florence Briggs Thayer) female 38.0 1 0 PC 17599 71.2833 C85 C
3 1 3 Heikkinen, Miss. Laina female 26.0 0 0 STON/O2. 3101282 7.925 None S
*/
Thought:There is an Age column in the titanic table. I should write a query to calculate the average age and then find the square root of the result.
Action: query_checker_sql_db
Action Input: SELECT SQRT(AVG(Age)) as square_root_of_avg_age FROM titanic
Observation: The original query seems to be correct. Here it is again:
SELECT SQRT(AVG(Age)) as square_root_of_avg_age FROM titanic
Thought:The query is correct, so I can execute it to find the square root of the average age.
Action: query_sql_db
Action Input: SELECT SQRT(AVG(Age)) as square_root_of_avg_age FROM titanic
Observation: [('5.449689683556195',)]
Thought:I now know the final answer
Final Answer: The square root of the average age is approximately 5.45.
> Finished chain.
'The square root of the average age is approximately 5.45.'
agent_executor.run("What's the name of the oldest survived passenger?")
> Entering new AgentExecutor chain...
Action: list_tables_sql_db
Action Input:
Observation: titanic
Thought:I should check the schema of the titanic table to see what columns are available.
Action: schema_sql_db
Action Input: titanic
Observation: CREATE TABLE langchain_example.titanic (
PassengerId INT,
Survived INT,
Pclass INT,
Name STRING,
Sex STRING,
Age DOUBLE,
SibSp INT,
Parch INT,
Ticket STRING,
Fare DOUBLE,
Cabin STRING,
Embarked STRING)
;
/*
3 rows from titanic table:
PassengerId Survived Pclass Name Sex Age SibSp Parch Ticket Fare Cabin Embarked
1 0 3 Braund, Mr. Owen Harris male 22.0 1 0 A/5 21171 7.25 None S
2 1 1 Cumings, Mrs. John Bradley (Florence Briggs Thayer) female 38.0 1 0 PC 17599 71.2833 C85 C
3 1 3 Heikkinen, Miss. Laina female 26.0 0 0 STON/O2. 3101282 7.925 None S
*/
Thought:I can use the titanic table to find the oldest survived passenger. I will query the Name and Age columns, filtering by Survived and ordering by Age in descending order.
Action: query_checker_sql_db
Action Input: SELECT Name, Age FROM titanic WHERE Survived = 1 ORDER BY Age DESC LIMIT 1
Observation: SELECT Name, Age FROM titanic WHERE Survived = 1 ORDER BY Age DESC LIMIT 1
Thought:The query is correct. Now I will execute it to find the oldest survived passenger.
Action: query_sql_db
Action Input: SELECT Name, Age FROM titanic WHERE Survived = 1 ORDER BY Age DESC LIMIT 1
Observation: [('Barkworth, Mr. Algernon Henry Wilson', '80.0')]
Thought:I now know the final answer.
Final Answer: The oldest survived passenger is Barkworth, Mr. Algernon Henry Wilson, who was 80 years old.
> Finished chain.
'The oldest survived passenger is Barkworth, Mr. Algernon Henry Wilson, who was 80 years old.'
连接这些文档 到 Claude、VSCode 等，通过 MCP 获取实时答案。