Create an Excel File (.xlsx) using PL/SQL

Question

In relation to my previous question Return the SQL Statement of an Explicit Cursor, i was able to generate an Excel (.xls) file using DBMS_SQL and UTL_FILE and passing a SYS_REFCURSOR (code is in the previous question). However, one challenge i'm encountering is the generated file is over 25 MB. I will be transmitting this over Email to Business Users and it would surely fill up their mailbox size. When I do manual extracts to xlsx using SQL Developer it just generates around 4 MB of data.

To Address this, would it be possible through PL/SQL to do the following?

1. Generate a file using a later version of Excel (.xlsx) to compress the size
2. Compress the .xls file before transmitting

I've also reviewed similar posts here in SO such as Writing in ExcelSheet using UTL_FILE package in Oracle, but as the answer stated, it needs to use Java. So its not applicable to me. Another post, Create an Excel Spreadsheet from a Oracle Database, is also using xls. So its not applicable as well.

Any thoughts?

Oracle Version:

Oracle Database 11g Enterprise Edition Release 11.2.0.4.0 - 64bit Production
PL/SQL Release 11.2.0.4.0 - Production
"CORE   11.2.0.4.0  Production"
TNS for Solaris: Version 11.2.0.4.0 - Production
NLSRTL Version 11.2.0.4.0 - Production

Answer 1

I've seen a package called as_xlsx by Anton Scheffer, Create an Excel-file with PL/SQL and it addressed my problem. I also modified it a bit to put in Worksheet Names and to allow SYS_REFCURSOR as a Parameter instead of a VARCHAR2 as required in my Previous Post (Return the SQL Statement of an Explicit Cursor).

I added this in the Package Specification for Procedure Overloading:

procedure query2sheet
( p_cur             IN OUT      SYS_REFCURSOR
, p_column_headers  boolean     := true
, p_directory       varchar2    := null
, p_filename        varchar2    := null
, p_sheet           pls_integer := null
, p_sheetname       varchar2    := null
);

I added this in the Package Body for Procedure Overloading (note: the line comments were lines I modified):

procedure query2sheet
( p_cur IN OUT SYS_REFCURSOR
, p_column_headers boolean := true
, p_directory varchar2 := null
, p_filename  varchar2 := null
, p_sheet     pls_integer := null
, p_sheetname varchar2 := null
)
is
    t_sheet     pls_integer;
    t_c         integer;
    t_col_cnt   integer;
    t_desc_tab2 dbms_sql.desc_tab2;
    t_desc_tab  dbms_sql.desc_tab;
    d_tab       dbms_sql.date_table;
    n_tab       dbms_sql.number_table;
    v_tab       dbms_sql.varchar2_table;
    t_bulk_size pls_integer := 200;
    t_r         integer;
    t_cur_row   pls_integer;
    t_d         number;
begin
    -- Changed
    if p_sheetname is not null then
        new_sheet(p_sheetname);      
    else
        new_sheet;
    end if;
    -- End of Change
    --t_c := dbms_sql.open_cursor;                       
    --dbms_sql.parse( t_c, p_sql, dbms_sql.native );

    t_d := DBMS_SQL.TO_CURSOR_NUMBER(p_cur);

    --dbms_sql.describe_columns2( t_c, t_col_cnt, t_desc_tab );
    dbms_sql.describe_columns( t_d, t_col_cnt, t_desc_tab );

    for c in 1 .. t_col_cnt
    loop
        if p_column_headers
        then
        cell( c, 1, t_desc_tab( c ).col_name, p_sheet => t_sheet );
        end if;
        --dbms_output.put_line( t_desc_tab( c ).col_name || ' ' || t_desc_tab( c ).col_type );
        case
        when t_desc_tab( c ).col_type in ( 2, 100, 101 )
        then
            --dbms_sql.define_array( t_c, c, n_tab, t_bulk_size, 1 );
            dbms_sql.define_array( t_d, c, n_tab, t_bulk_size, 1 );
        when t_desc_tab( c ).col_type in ( 12, 178, 179, 180, 181 , 231 )
        then
            --dbms_sql.define_array( t_c, c, d_tab, t_bulk_size, 1 );
            dbms_sql.define_array( t_d, c, d_tab, t_bulk_size, 1 );
        when t_desc_tab( c ).col_type in ( 1, 8, 9, 96, 112 )
        then
            --dbms_sql.define_array( t_c, c, v_tab, t_bulk_size, 1 );
            dbms_sql.define_array( t_d, c, v_tab, t_bulk_size, 1 );
        else
            null;
        end case;
    end loop;
    --
    t_cur_row := case when p_column_headers then 2 else 1 end;
    t_sheet := nvl( p_sheet, workbook.sheets.count() );
    --
    --t_r := dbms_sql.execute( t_c );
    loop
        --t_r := dbms_sql.fetch_rows( t_c );
        t_r := dbms_sql.fetch_rows( t_d );
        if t_r > 0
        then
        for c in 1 .. t_col_cnt
        loop
            case
            when t_desc_tab( c ).col_type in ( 2, 100, 101 )
            then
                --dbms_sql.column_value( t_c, c, n_tab );
                dbms_sql.column_value( t_d, c, n_tab );
                for i in 0 .. t_r - 1
                loop
                if n_tab( i + n_tab.first() ) is not null
                then
                    cell( c, t_cur_row + i, n_tab( i + n_tab.first() ), p_sheet => t_sheet );
                end if;
                end loop;
                n_tab.delete;
            when t_desc_tab( c ).col_type in ( 12, 178, 179, 180, 181 , 231 )
            then
                --dbms_sql.column_value( t_c, c, d_tab );
                dbms_sql.column_value( t_d, c, d_tab );
                for i in 0 .. t_r - 1
                loop
                if d_tab( i + d_tab.first() ) is not null
                then
                    cell( c, t_cur_row + i, d_tab( i + d_tab.first() ), p_sheet => t_sheet );
                end if;
                end loop;
                d_tab.delete;
            when t_desc_tab( c ).col_type in ( 1, 8, 9, 96, 112 )
            then
                --dbms_sql.column_value( t_c, c, v_tab );
                dbms_sql.column_value( t_d, c, v_tab );
                for i in 0 .. t_r - 1
                loop
                if v_tab( i + v_tab.first() ) is not null
                then
                    cell( c, t_cur_row + i, v_tab( i + v_tab.first() ), p_sheet => t_sheet );
                end if;
                end loop;
                v_tab.delete;
            else
                null;
            end case;
        end loop;
        end if;
        exit when t_r != t_bulk_size;
        t_cur_row := t_cur_row + t_r;
    end loop;
    --dbms_sql.close_cursor( t_c );
    dbms_sql.close_cursor( t_d );
    if ( p_directory is not null and  p_filename is not null )
    then
        save( p_directory, p_filename );
    end if;
exception
when others
then
    --if dbms_sql.is_open( t_c )
    if dbms_sql.is_open( t_d )
    then
    --dbms_sql.close_cursor( t_c );
    dbms_sql.close_cursor( t_d );
    end if;
end query2sheet;

This is a Sample Block in my Concurrent Request that Creates the File:

Procedure EMP_ROSTER_REPORT (p_empno        per_all_people_f.employee_number%type                              
                           , p_bg_id        per_business_groups.business_group_id%type
                           , p_email_add    per_all_people_f.email_address%type)
is

    l_fh            UTL_FILE.FILE_TYPE;
    l_directory     VARCHAR2(30) := 'EXT_TAB_DATA';
    l_filename      VARCHAR2(100);
    emp_cur         SYS_REFCURSOR;
    l_message       varchar2(100);
    g_stage         varchar2(100);
    g_zipped_blob   blob;

    cursor  p_payroll_cur is
    select  payroll_id
        ,   payroll_name
        ,   business_group_id
    from    pay_all_payrolls_f
    where   business_group_id = p_bg_id;

BEGIN

    -----------------------------------
    g_stage := 'setting the filename';
    -----------------------------------

    l_filename := 'EMPLOYEE_ROSTER_REPORT_'||TO_CHAR(SYSDATE, 'DD-MON-YYYY-HHMISS');

    ------------------------------------------
    g_stage := 'Assigning Emp SysRefCursor';
    ------------------------------------------

    for i in p_payroll_cur loop

        OPEN emp_cur FOR
        SELECT  'extra long query here with parameters'
        from    table_a
        where   payroll_id = i.payroll_id;

        ----------------------------------------------------------
        g_stage := 'open Employee Cursor and write into the File';
        ----------------------------------------------------------

        as_xlsx.query2sheet( p_cur          => emp_cur            -- Uses Sys_RefCursor Instead of Dynamic SQL (Varchar2)
                           , p_sheetname    => i.payroll_name);   -- This is where we assign the Sheet Names         
        as_xlsx.freeze_pane( 1,1 );                               -- Freeze the topmost and rightmost pane in the Excel Sheet

    end loop;

    ------------------------------
    g_stage := 'Create the File';
    ------------------------------

    as_xlsx.save( l_directory , l_filename||'.xlsx');

END EMP_ROSTER_REPORT;

Hope this helps someone! :)