56 lines
1.8 KiB
Python
56 lines
1.8 KiB
Python
#------------------------------------------------------------------------------
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# Copyright (c) 2018, 2020, Oracle and/or its affiliates. All rights reserved.
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#------------------------------------------------------------------------------
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#------------------------------------------------------------------------------
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# RefCursor.py
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# Demonstrates the use of REF cursors with cx_Oracle.
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#------------------------------------------------------------------------------
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import cx_Oracle
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import sample_env
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connection = cx_Oracle.connect(sample_env.get_main_connect_string())
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cursor = connection.cursor()
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ref_cursor = connection.cursor()
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cursor.callproc("myrefcursorproc", (2, 6, ref_cursor))
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print("Rows between 2 and 6:")
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for row in ref_cursor:
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print(row)
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print()
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ref_cursor = connection.cursor()
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cursor.callproc("myrefcursorproc", (8, 9, ref_cursor))
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print("Rows between 8 and 9:")
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for row in ref_cursor:
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print(row)
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print()
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#------------------------------------------------------------------------------
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# Setting prefetchrows and arraysize of a REF cursor can improve performance
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# when fetching a large number of rows (Tuned Fetch)
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#------------------------------------------------------------------------------
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# Truncate the table used for this demo
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cursor.execute("truncate table TestTempTable")
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# Populate the table with a large number of rows
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num_rows = 50000
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sql = "insert into TestTempTable (IntCol) values (:1)"
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data = [(n + 1,) for n in range(num_rows)]
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cursor.executemany(sql, data)
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# Set the arraysize and prefetch rows of the REF cursor
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ref_cursor = connection.cursor()
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ref_cursor.prefetchrows = 1000
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ref_cursor.arraysize = 1000
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# Perform the tuned fetch
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sum_rows = 0
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cursor.callproc("myrefcursorproc2", [ref_cursor])
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print("Sum of IntCol for", num_rows, "rows:")
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for row in ref_cursor:
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sum_rows += row[0]
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print(sum_rows)
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