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| # Registering Views | |
| You can use the context's `register_view` method to register a DataFrame as a view | |
| ```python | |
| from datafusion import SessionContext, col, literal | |
| # Create a DataFusion context | |
| ctx = SessionContext() | |
| # Create sample data | |
| data = {"a": [1, 2, 3, 4, 5], "b": [10, 20, 30, 40, 50]} | |
| # Create a DataFrame from the dictionary | |
| df = ctx.from_pydict(data, "my_table") | |
| # Filter the DataFrame (for example, keep rows where a > 2) | |
| df_filtered = df.filter(col("a") > literal(2)) | |
| # Register the dataframe as a view with the context | |
| ctx.register_view("view1", df_filtered) | |
| # Now run a SQL query against the registered view | |
| df_view = ctx.sql("SELECT * FROM view1") | |
| # Collect the results | |
| results = df_view.collect() | |
| # Convert results to a list of dictionaries for display | |
| result_dicts = [batch.to_pydict() for batch in results] | |
| print(result_dicts) | |
| ``` | |
| This will output: | |
| ```python | |
| [{'a': [3, 4, 5], 'b': [30, 40, 50]}] | |
| ``` |