49 lines
1.8 KiB
Python
49 lines
1.8 KiB
Python
#------------------------------------------------------------------------------
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# Copyright (c) 2016, 2021, Oracle and/or its affiliates. All rights reserved.
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#------------------------------------------------------------------------------
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#------------------------------------------------------------------------------
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# array_dml_rowcounts.py
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#
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# Demonstrate the use of the 12.1 feature that allows cursor.executemany()
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# to return the number of rows affected by each individual execution as a list.
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# The parameter "arraydmlrowcounts" must be set to True in the call to
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# cursor.executemany() after which cursor.getarraydmlrowcounts() can be called.
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#
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# This script requires cx_Oracle 5.2 and higher.
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#------------------------------------------------------------------------------
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import cx_Oracle as oracledb
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import sample_env
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connection = oracledb.connect(sample_env.get_main_connect_string())
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cursor = connection.cursor()
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# show the number of rows for each parent ID as a means of verifying the
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# output from the delete statement
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for parent_id, count in cursor.execute("""
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select ParentId, count(*)
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from ChildTable
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group by ParentId
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order by ParentId"""):
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print("Parent ID:", parent_id, "has", int(count), "rows.")
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print()
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# delete the following parent IDs only
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parent_ids_to_delete = [20, 30, 50]
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print("Deleting Parent IDs:", parent_ids_to_delete)
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print()
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# enable array DML row counts for each iteration executed in executemany()
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cursor.executemany("""
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delete from ChildTable
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where ParentId = :1""",
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[(i,) for i in parent_ids_to_delete],
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arraydmlrowcounts = True)
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# display the number of rows deleted for each parent ID
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row_counts = cursor.getarraydmlrowcounts()
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for parent_id, count in zip(parent_ids_to_delete, row_counts):
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print("Parent ID:", parent_id, "deleted", count, "rows.")
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