XiaoHongbo-Hope commented on code in PR #7599: URL: https://github.com/apache/paimon/pull/7599#discussion_r3039010437
########## paimon-python/pypaimon/sql/sql_context.py: ########## @@ -0,0 +1,79 @@ +# Licensed to the Apache Software Foundation (ASF) under one +# or more contributor license agreements. See the NOTICE file +# distributed with this work for additional information +# regarding copyright ownership. The ASF licenses this file +# to you under the Apache License, Version 2.0 (the +# "License"); you may not use this file except in compliance +# with the License. You may obtain a copy of the License at +# +# http://www.apache.org/licenses/LICENSE-2.0 +# +# Unless required by applicable law or agreed to in writing, +# software distributed under the License is distributed on an +# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY +# KIND, either express or implied. See the License for the +# specific language governing permissions and limitations +# under the License. + +import pyarrow as pa + + +class SQLContext: + """SQL query context for Paimon tables. + + Uses pypaimon-rust and DataFusion to execute SQL queries against Paimon tables. + Supports registering multiple catalogs for cross-catalog queries. + + Example:: + + from pypaimon.sql import SQLContext + + ctx = SQLContext() + ctx.register_catalog("paimon", {"warehouse": "/path/to/warehouse"}) + ctx.set_current_catalog("paimon") + ctx.set_current_database("default") + result = ctx.sql("SELECT * FROM my_table") + """ + + def __init__(self): + try: + from datafusion import SessionContext + except ImportError: + raise ImportError( + "datafusion is required for SQL query support. " + "Install it with: pip install pypaimon[sql]" + ) + + self._ctx = SessionContext() + + def register_catalog(self, name, options): + """Register a Paimon catalog as a DataFusion catalog provider. + + Args: + name: The catalog name to register under. + options: A dict of catalog options (e.g. {"warehouse": "/path/to/warehouse"}). + """ + try: + from pypaimon_rust.datafusion import PaimonCatalog + except ImportError: + raise ImportError( + "pypaimon-rust is required for SQL query support. " + "Install it with: pip install pypaimon[sql]" + ) + + paimon_catalog = PaimonCatalog(options) + self._ctx.register_catalog_provider(name, paimon_catalog) + + def set_current_catalog(self, catalog_name: str): + """Set the default catalog for SQL queries.""" + self._ctx.sql(f"SET datafusion.catalog.default_catalog = '{catalog_name}'") + + def set_current_database(self, database: str): + """Set the default database for SQL queries.""" + self._ctx.sql(f"SET datafusion.catalog.default_schema = '{database}'") + + def sql(self, query: str) -> pa.Table: + """Execute a SQL query and return the result as a PyArrow Table.""" + df = self._ctx.sql(query) + batches = df.collect() + return pa.Table.from_batches(batches) Review Comment: This may raise ValueError when the query returns empty results. Could you please add a case to cover it. -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
