Batching

Determining If a Database Supports Batching
Executing a Batch of SQL Statements in a Database

Determining If a Database Supports Batching

With batch updating, a set of SQL statements is assembled and then sent altogether to the database for execution. Batch updating can improve performance.

COPY

try {
    DatabaseMetaData dmd = connection.getMetaData();
    if (dmd.supportsBatchUpdates()) {
        // Batching is supported
    } else {
        // Batching is not supported
    }
} catch (SQLException e) {
}

Executing a Batch of SQL Statements in a Database

With batch updating, a set of SQL statements is assembled and then sent altogether to the database for execution. Batch updating can improve performance.

This example creates a batch of insert statements. Auto-commit is disabled so that you have the choice of committing or not in the event of an exception.

COPY

try {
    // Disable auto-commit
    connection.setAutoCommit(false);

    // Create a prepared statement
    String sql = "INSERT INTO my_table VALUES(?)";
    PreparedStatement pstmt = connection.prepareStatement(sql);

    // Insert 10 rows of data
    for (int i=0; i<10; i++) {
        pstmt.setString(1, ""+i);
        pstmt.addBatch();
    }

    // Execute the batch
    int [] updateCounts = pstmt.executeBatch();

    // All statements were successfully executed.
    // updateCounts contains one element for each batched statement.
    // updateCounts[i] contains the number of rows affected by that statement.
    processUpdateCounts(updateCounts);

    // Since there were no errors, commit
    connection.commit();
} catch (BatchUpdateException e) {
    // Not all of the statements were successfully executed
    int[] updateCounts = e.getUpdateCounts();

    // Some databases will continue to execute after one fails.
    // If so, updateCounts.length will equal the number of batched statements.
    // If not, updateCounts.length will equal the number of successfully executed statements
    processUpdateCounts(updateCounts);

    // Either commit the successfully executed statements or rollback the entire batch
    connection.rollback();
} catch (SQLException e) {
}

public static void processUpdateCounts(int[] updateCounts) {
    for (int i=0; i= 0) {
            // Successfully executed; the number represents number of affected rows
        } else if (updateCounts[i] == Statement.SUCCESS_NO_INFO) {
            // Successfully executed; number of affected rows not available
        } else if (updateCounts[i] == Statement.EXECUTE_FAILED) {
            // Failed to execute
        }
    }
}