Google BigQuery

Google BigQuery 是一款跨云且可根据您的数据规模扩展的无服务器且经济高效的企业数据仓库。BigQuery 是 Google Cloud Platform 的一部分。

加载一个每行一个文档的 BigQuery 查询。

%pip install --upgrade --quiet langchain-google-community[bigquery]

from langchain_google_community import BigQueryLoader

BASE_QUERY = """
SELECT
  id,
  dna_sequence,
  organism
FROM (
  SELECT
    ARRAY (
    SELECT
      AS STRUCT 1 AS id, "ATTCGA" AS dna_sequence, "Lokiarchaeum sp. (strain GC14_75)." AS organism
    UNION ALL
    SELECT
      AS STRUCT 2 AS id, "AGGCGA" AS dna_sequence, "Heimdallarchaeota archaeon (strain LC_2)." AS organism
    UNION ALL
    SELECT
      AS STRUCT 3 AS id, "TCCGGA" AS dna_sequence, "Acidianus hospitalis (strain W1)." AS organism) AS new_array),
  UNNEST(new_array)
"""

基本用法

loader = BigQueryLoader(BASE_QUERY)

data = loader.load()

print(data)

[Document(page_content='id: 1\ndna_sequence: ATTCGA\norganism: Lokiarchaeum sp. (strain GC14_75).', lookup_str='', metadata={}, lookup_index=0), Document(page_content='id: 2\ndna_sequence: AGGCGA\norganism: Heimdallarchaeota archaeon (strain LC_2).', lookup_str='', metadata={}, lookup_index=0), Document(page_content='id: 3\ndna_sequence: TCCGGA\norganism: Acidianus hospitalis (strain W1).', lookup_str='', metadata={}, lookup_index=0)]

指定哪些列是内容与元数据

loader = BigQueryLoader(
    BASE_QUERY,
    page_content_columns=["dna_sequence", "organism"],
    metadata_columns=["id"],
)

data = loader.load()

print(data)

[Document(page_content='dna_sequence: ATTCGA\norganism: Lokiarchaeum sp. (strain GC14_75).', lookup_str='', metadata={'id': 1}, lookup_index=0), Document(page_content='dna_sequence: AGGCGA\norganism: Heimdallarchaeota archaeon (strain LC_2).', lookup_str='', metadata={'id': 2}, lookup_index=0), Document(page_content='dna_sequence: TCCGGA\norganism: Acidianus hospitalis (strain W1).', lookup_str='', metadata={'id': 3}, lookup_index=0)]

将源添加到元数据

# Note that the `id` column is being returned twice, with one instance aliased as `source`
ALIASED_QUERY = """
SELECT
  id,
  dna_sequence,
  organism,
  id as source
FROM (
  SELECT
    ARRAY (
    SELECT
      AS STRUCT 1 AS id, "ATTCGA" AS dna_sequence, "Lokiarchaeum sp. (strain GC14_75)." AS organism
    UNION ALL
    SELECT
      AS STRUCT 2 AS id, "AGGCGA" AS dna_sequence, "Heimdallarchaeota archaeon (strain LC_2)." AS organism
    UNION ALL
    SELECT
      AS STRUCT 3 AS id, "TCCGGA" AS dna_sequence, "Acidianus hospitalis (strain W1)." AS organism) AS new_array),
  UNNEST(new_array)
"""

loader = BigQueryLoader(ALIASED_QUERY, metadata_columns=["source"])

data = loader.load()

print(data)

[Document(page_content='id: 1\ndna_sequence: ATTCGA\norganism: Lokiarchaeum sp. (strain GC14_75).\nsource: 1', lookup_str='', metadata={'source': 1}, lookup_index=0), Document(page_content='id: 2\ndna_sequence: AGGCGA\norganism: Heimdallarchaeota archaeon (strain LC_2).\nsource: 2', lookup_str='', metadata={'source': 2}, lookup_index=0), Document(page_content='id: 3\ndna_sequence: TCCGGA\norganism: Acidianus hospitalis (strain W1).\nsource: 3', lookup_str='', metadata={'source': 3}, lookup_index=0)]

相关

• 文档加载器 概念指南
• 文档加载器 操作指南