langchain/tests/unit_tests/test_sql_database_schema.py
Harrison Chase 95157d0aad
Add schema property to sql database utility class (#448) (#462)
Co-authored-by: Harrison Chase <hw.chase.17@gmail.com>

Signed-off-by: Diwank Singh Tomer <diwank.singh@gmail.com>
Co-authored-by: Nuno Campos <nuno@boringbits.io>
Co-authored-by: Diwank Singh Tomer <diwank.singh@gmail.com>
2022-12-28 17:37:53 -05:00

67 lines
1.8 KiB
Python

"""Test SQL database wrapper with schema support.
Using DuckDB as SQLite does not support schemas.
"""
from sqlalchemy import (
Column,
Integer,
MetaData,
Sequence,
String,
Table,
create_engine,
event,
insert,
schema,
)
from langchain.sql_database import SQLDatabase
metadata_obj = MetaData()
event.listen(metadata_obj, "before_create", schema.CreateSchema("schema_a"))
event.listen(metadata_obj, "before_create", schema.CreateSchema("schema_b"))
user = Table(
"user",
metadata_obj,
Column("user_id", Integer, Sequence("user_id_seq"), primary_key=True),
Column("user_name", String, nullable=False),
schema="schema_a",
)
company = Table(
"company",
metadata_obj,
Column("company_id", Integer, Sequence("company_id_seq"), primary_key=True),
Column("company_location", String, nullable=False),
schema="schema_b",
)
def test_table_info() -> None:
"""Test that table info is constructed properly."""
engine = create_engine("duckdb:///:memory:")
metadata_obj.create_all(engine)
db = SQLDatabase(engine, schema="schema_a")
output = db.table_info
expected_output = (
"Table 'user' has columns: user_id (INTEGER), user_name (VARCHAR).",
)
assert sorted(output.split("\n")) == sorted(expected_output)
def test_sql_database_run() -> None:
"""Test that commands can be run successfully and returned in correct format."""
engine = create_engine("duckdb:///:memory:")
metadata_obj.create_all(engine)
stmt = insert(user).values(user_id=13, user_name="Harrison")
with engine.connect() as conn:
conn.execute(stmt)
db = SQLDatabase(engine, schema="schema_a")
command = 'select user_name from "user" where user_id = 13'
output = db.run(command)
expected_output = "[('Harrison',)]"
assert output == expected_output