URGENT -- Perofrmance issue while creating Huge XML file

Question

All XML Experts Please Help....Thanks a lot in Advance
We are trying to create a XML file for a huge table.. 5 million rows and the performance is ver very bad.. Can some body help by giving me an idea what what my best approch could be... or what am I doing wrong in in the code below
CREATE OR REPLACE PROCEDURE Sales_1_Generate_Xml IS
temp_clob CLOB;
temp_buffer VARCHAR2(1);
amount BINARY_INTEGER := 1;
position INTEGER := 1;
filehandle utl_file.file_type;
error_number NUMBER;
error_message VARCHAR2(100);
length_count INTEGER;
qryctx dbms_xmlgen.ctxhandle;
BEGIN
qryctx := dbms_xmlgen.newcontext('select /* INDEX UF_SALES(UF_SALES_IX16) */
TRANSACTION_NUMBER     "Transaction_Number",
TRANSACTION_TYPE_ID     "Transaction_Type_ID",
PROCESS_FISCAL_DATE_ID     "Process_Fiscal_Date_ID",
INVOICE_FISCAL_DATE_ID     "Invoice_Fiscal_Date_ID",
ORDER_FISCAL_DATE_ID     "Order_Fiscal_Date_ID",
PROCESS_CALENDAR_DATE_ID     "Process_Calendar_Date_ID",
INVOICE_CALENDAR_DATE_ID     "Invoice_Calendar_Date_ID",
ORDER_CALENDAR_DATE_ID     "Order_Calendar_Date_ID",
CURRENT_TM_ID     "Current_TM_ID",
CUSTOMER_ID     "Customer_ID",
CUSTOMER_TYPE_ID     "Customer_Type_ID",
CUSTOMER_LEVEL_ID     "Customer_Level_ID",
ACCOUNT_TYPE_ID     "Account_Type_ID",
TRADE_CLASS_ID     "Trade_Class_ID",
DISTRIBUTOR_ID     "Distributor_ID",
PRODUCT_ID     "Product_ID",
ORDERED_PRODUCT_ID     "Ordered_Product_ID",
BRAND_TYPE_ID     "Brand_Type_ID",
LABEL_TYPE_ID     "Label_Type_ID",
BRAND_LABEL_ID     "Brand_Label_ID",
PRICED_BY_ID     "Priced_By_ID",
SALES_UOM_ID     "Sales_UOM_ID",
PURCHASING_UOM_ID     "Purchasing_UOM_ID",
PRICING_UOM_ID     "Pricing_UOM_ID",
NET_COST     "Net_Cost",
NPA_S     "NPA_S",
CMA_S     "CMA_S",
NOT_S     "NOT_S",
TOTAL_NATIONAL_ALLOWANCE_S     "Total_National_Allowance_S",
LPA_S     "LPA_S",
LMA_S     "LMA_S",
LOT_S     "LOT_S",
TOTAL_LOCAL_ALLOWANCE_S     "Total_Local_Allowance_S",
TOTAL_ALLOWANCES_S     "Total_Allowances_S",
LPC     "LPC",
LPC_EXTENDED     "LPC_Extended",
LPF     "LPF",
LPF_EXTENDED     "LPF_Extended",
TRUE_COST     "True_Cost",
CDE     "CDE",
LPP     "LPP",
SURCHARGE     "Surcharge",
COMBINED_SURCHARGE     "Combined_Surcharge",
TOTAL_SURCHARGES     "Total_Surcharges",
MARKET_COST     "Market_Cost",
INSIDE_PAD     "Inside_Pad",
SALES_REP_COST     "Sales_Rep_Cost",
SALES_REP_MARGIN     "Sales_Rep_Margin",
SALES_PRICE     "Sales_Price",
SALES_TRUE_MARGIN     "Sales_True_Margin",
NVD     "NVD",
LVD     "LVD",
NID     "NID",
LID     "LID",
TOTAL_VD     "Total_VD",
TOTAL_ID     "Total_ID",
TOTAL_DEVIATIONS     "Total_Deviations",
GP1     "GP1",
GP2     "GP2",
DEVIATED_COST     "Deviated_Cost",
ACTUAL_COST     "Actual_Cost",
SALES_TAX     "Sales_Tax",
QUANTITY_ORDERED     "Quantity_Ordered",
QUANTITY_SHIPPED     "Quantity_Shipped",
QUANTITY_DEVIATED     "Quantity_Deviated",
QUANTITY_SUBBED     "Quantity_Subbed",
UNITS_ORDERED     "Units_Ordered",
EACHES_ORDERED     "Eaches_Ordered",
EACH_CONVERSION_FACTOR     "Each_Conversion_Factor",
UNITS_SHIPPED     "Units_Shipped",
EACHES_SHIPPED     "Eaches_Shipped",
SHIP_WEIGHT     "Ship_Weight",
ACTUAL_GP_DLR     "Actual_GP_Dlr",
TRUE_GP_DLR     "True_GP_Dlr",
LANDED_GP_DLR     "Landed_GP_Dlr",
LANDED_ACTUAL_GP_DLR     "Landed_Actual_GP_Dlr",
INVOICE_GP_DLR     "Invoice_GP_Dlr",
INVOICE_ACTUAL_GP_DLR     "Invoice_Actual_GP_Dlr",
ADJUSTED_ACTUAL_GP_DLR     "Adjusted_Actual_GP_Dlr",
EB_S     "EB_S",
MB_S     "MB_S",
ACTUAL_TM_ID     "Actual_TM_ID",
ACTUAL_TM_NAME     "Actual_TM_Name",
ACTUAL_DSM_ID     "Actual_DSM_ID",
ACTUAL_DSM_NAME     "Actual_DSM_Name",
INVOICE_NUMBER      "Invoice_Number ",
CONTRACT_NUMBER     "Contract_Number",
CUSTOMER_NUMBER     "Customer_Number",
CUSTOMER     "Customer",
PRODUCT_NUMBER     "Product_Number",
MASTER_DISTRIBUTOR_ID     "Master_Distributor_ID",
ORDERED_PRODUCT_NUMBER     "Ordered_Product_Number",
NATIVE_PRODUCT_STATUS     "Native_Product_Status",
NATIVE_PRICED_BY_INDICATOR     "Native_Priced_By_Indicator",
EXTRACTION_TIME     "Extraction_Time"
from uf_sales where distributor_id in (''5139'',
''5140'',
''5145'',
''5150'',
''5160'',
''5175'',
''5180'',
''5210'',
''5220'',
''5230'')
DBMS_XMLGen.setRowTag(qryctx,'Sales_Record');
DBMS_XMLGen.setRowSetTag(qryctx,'Sales_Set');
temp_clob:=dbms_xmlgen.getxml(qryctx);
length_count := dbms_lob.getlength(temp_clob);
dbms_output.put_line('Internal LOB size is: ' || length_count);
filehandle := utl_file.fopen('DATA_EXTRACT','Sales_1.xml','Wb',32767);
WHILE length_count <> 0 LOOP
dbms_lob.read (temp_clob, amount, position, temp_buffer);
--utl_file.put (filehandle, temp_buffer);
utl_file.put_raw(filehandle, utl_raw.cast_to_raw(temp_buffer));
position := position + 1;
length_count := length_count - 1;
temp_buffer := null;
END LOOP;
dbms_output.put_line('Exit the loop');
utl_file.fclose(filehandle);
DBMS_XMLGen.closeContext(qryctx);
dbms_output.put_line('Close the file');
EXCEPTION
WHEN OTHERS THEN
BEGIN
error_number := sqlcode;
error_message := substr(sqlerrm ,1 ,100);
dbms_output.put_line('Error #: ' || error_number);
dbms_output.put_line('Error Message: ' || error_message);
utl_file.fclose_all;
END;
END;
/

Answer 1

OK, so you are writing the file with UTL_FILE. How long is the whole process taking. Have you timed the time taken to generate the temp_clob with the result Vs the time to write the output to a file.