Elapsed: You can also catch regular content via Connor's blog and Chris's blog. Or if video is more your thing, check out Connor's latest video and Chris's latest video from their Youtube channels. And of course, keep up to date with AskTOM via the official twitter account. Questions Bulk Update Performance Tuning. Question and Answer. CHAR: case Types. DATE: return resultSet. TIME: return resultSet. CLOB: return resultSet. BLOB: return resultSet. REAL: return resultSet.
BIT: case Types. REF: return resultSet. Improve this question. Bren Bren 2, 1 1 gold badge 27 27 silver badges 39 39 bronze badges. Where does insertScript come from, and does it do any explicit or indeed implicit conversions? The only difference in the tables that jumps out is the timestamps in the second one; are they present in all the slow ones? And as an aside, did you consider using data pump to to the transfer over a database link, via the API if you want it to be controlled from Java?
Well i build the insert script dynamically. All i do is "insert into target table cols values? I dont do conversion. And i did select 20 columns from that slow table other than timestamps, and it was still slow.
We are going to make it copy data between different db platforms. And we do data masking too if defined. Thats why we are using java, and do it copy distributed. Do you have any indexes or constraints on the slow table?
JensSchauder Forgot to mention that, No i do not have any constraints or indexes on both tables. Add a comment. Active Oldest Votes. Just the way i use get methods Though, i didn't quite understand what exactly was the problem. Anyway i am happy i solved the problem. Thanks to all who replied.
If you enter a set of input values for a second operation and call executeUpdate again, then the data will still not be sent to the database, because the batch value in effect for the statement is the connection batch value, which is Note that the value of rows in the println statement is 0. If you apply the sendBatch method at this point, then the two previously batched operations will be sent to the database in a single round trip. The sendBatch method also returns the total number of updated rows.
This property of sendBatch is used by println to print the number of updated rows. Comm itting the Changes in Oracle Batching. After you process the batch, you must still commit the changes, presuming auto-commit is disabled as recommended.
Calling commit on the connection object in Oracle batching not only commits operations in batches that have been processed, but also issues an implicit sendBatch call to process all pending batches. So commit effectively commits changes for all operations that have been added to a batch.
Update Counts in Oracle Batching. In a non-batching situation, the executeUpdate method of an OraclePreparedStatement object will return the number of database rows affected by the operation.
In an Oracle batching situation, this method returns the number of rows affected at the time the method is invoked, as follows:. If an executeUpdate call results in the operation being added to the batch, then the method returns a value of 0, because nothing was written to the database yet. If an executeUpdate call results in the batch value being reached and the batch being processed, then the method will return the total number of rows affected by all operations in the batch.
Similarly, the send Batch method of an OraclePreparedStatement object returns the total number of rows affected by all operations in the batch. Example Oracle Update Batching.
The following example illustrates how you use the Oracle update batching feature. It assumes you have imported the oracle. This model, unlike the Oracle update batching model, depends on explicitly adding statements to the batch using an addBatch method and explicitly processing the batch using an executeBatch method. In the Oracle model, you call executeUpdate as in a non-batching situation, but whether an operation is added to the batch or the whole batch is processed is typically determined implicitly, depending on whether a pre-determined batch value is reached.
Disable auto-commit mode if you use either update batching model. Limitations in the Oracle Implementation of Standard Batching. Note the following limitations and implementation details regarding the Oracle implementation of standard update batching:. In Oracle JDBC applications, update batching is intended for use with prepared statements that are being processed repeatedly with different sets of bind values.
The Oracle implementation of standard update batching does not implement true batching for generic statements and callable statements. Even though Oracle JDBC supports the use of standard batching for Statement and CallableStatement objects, you are unlikely to see performance improvement.
The Oracle implementation of stan dard update batching does not support stream types as bind values. Any attempt to use stream types will result in an exception. When any statement object is first created, its statement batch is empty. Use the standard ad dBatch method to add an operation to the statement batch. This method is specified in the standard java. Statement , PreparedStatement , and CallableStatement interfaces, which are implemented by the oracle. For example:. For prepared statements, update batching is used to batch multiple runs of the same statement with different sets of bind parameters.
It simply adds the operation to the batch using the bind parameters last set by the appropriate set XXX methods. This is also true for CallableStatement or OracleCallableStatement objects, but remember that in the Oracle implementation of standard update batching, you will probably see no performance improvement in batching callable statements. Because a batch is associated with a single prepared statement object, you can batch only repeated runs of a single prepared statement, as in this example.
To process the current batch of operations, use the exec uteBatch method of the statement object. This method is specified in the standard Statement interface, which is extended by the standard PreparedStatement and CallableStatement interfaces. Following is an example that repeats the prepared statement addBatch calls shown previously and then processes the batch:. The executeBatch method returns an int array, typically one element per batched operation, indicating success or failure in processing the batch and sometimes containing information about the number of rows affected.
After calling addBatch , you must call either executeBatch or clearBatch before a call to executeUpdate , otherwise there will be a SQL exception. You must explicitly call clearBatch to reset it. An executeBatch call closes the current result set of the statement object, if one exists. Calling commit , commits non-batched operations and batched operations for statement batches that have been processed, but for the Oracle implementation of standard batching, has no effect on pending statement batches that have not been processed.
To clear the current batch of operations instead of processing it, use the cle arBatch method of the statement object. Following is an example that repeats the prepared statement addBatch calls shown previously but then clears the batch under certain circumstances:. If a statement batch is processed successfully, then the integer array, or update counts array, returned by the statement executeBatch call will always have one element for each operation in the batch.
In the Oracle implementation of standard update batching, the values of the array elements are as follows:. For a prepared statement batch, it is not possible to know the number of rows affected in the database by each individual statement in the batch.
Therefore, all array elements have a value of According to the JDBC 2. For a generic statement batch the array contains the actual update counts indicating the number of rows affected by each operation. The actual update counts can be provided only in the case of generic statements in Oracle implementation of standard batching. For a callable statement batch, the server always returns the value 1 as the update count, irrespective of the number rows affected by each operation.
In your code, upon successful processing of a batch, you should be prepared to handle either -2 , 1 , or true update counts in the array elements. For a successful batch processing, the array contains either all -2 , 1, or all positive integers. Example Stan dard Update Batching. This example combines the sample fragments in the previous sections, accomplishing the following steps:. If any one of the batched operations fails to complete successfully or attempts to return a result set during an executeBatch call, then the processing stops and a java.
Batch UpdateException is generated. After a batch exception, the update counts array can be retrieved using the get UpdateCounts method of the BatchUpdateException object. This returns an int array of update counts, just as the executeBatch method does.
In the Oracle implementation of standard update batching, contents of the update counts array are as follows, after a batch is processed:. For a pr epared statement batch, it is not possible to know which operation failed. The array has one element for each operation in the batch, and each element has a value of In this case, it was presumably just one operation that actually failed, but because the JDBC driver does not know which operation that was, it labels all the batched operations as failures.
For a generic statement batch or callable statement batch, the update counts array is only a partial array containing the actual update counts up to the point of the error. The actual update counts can be provided because Oracle JDBC cannot use true batching for generic and callable statements in the Oracle implementation of standard update batching. For example, if there were 20 operations in the batch, the first 13 succeeded, and the 14th generated an exception, then the update counts array will have 13 elements, containing actual update counts of the successful operations.
In your code, upon failed processing of a batch, you should be prepared to handle either -3 or true update counts in the array elements when an exception occurs. For a failed batch processing, you will have either a full array of -3 or a partial array of positive integers. You cannot call executeUpdate for regular, non-batched processing of an operation if the statement object has a pending batch of operations. Feel free to ask questions on our Oracle forum.
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