Question

APEX 3.2
Oracle 11

My requirement is to create a GUI process that allows a user to load a .CSV file, which only has 4 columns and may have multiple rows. Then update the data table in the database with the corresponding data from the .CVS file.

CSV file:
ID Number:  Field Name:  Channel:   Analyst:
123456      Title         Retail    John Smith
123456      City          Retail    John Smith


Current DB:
ID Number:  Field Name:  Channel:   Analyst:
123456      Title         Retail    (null)
123456      City          (null)    (null)


After Update DB
ID Number:  Field Name:  Channel:   Analyst:
123456      Title         Retail    John Smith
123456      City          Retail    John Smith

Any ideas or links is appreciated.

Answer 1

Provide a file browse item, upload your files to wwv_flow_files.

Then parse the BLOB content, see this link:

http://christopherbeck.wordpress.com/2012/04/03/parsing-a-csv-file-in-plsql/

The comments are worth a read too. For example, the Alexendria PLSQL utility library is mentioned. This library contains lots and lots of tools which are plsql based, and is worth a damn good look!

http://code.google.com/p/plsql-utils/

(Quoted from Morten’s comment in the blog)

Chris,

As I pointed out, the latest version of the csv_util_pkg package can
be found in the Alexandria library, and this does indeed support
optionally enclosed values.

I just tested it with your example data:

 select * from table(csv_util_pkg.clob_to_csv(‘normal,”commas,,,in the
 field”,”"”enclosed”"”,”random “” double “” quotes”,”commas,,, “” and
 double “”"” quotes”‘))

And this splits the data into 5 columns:

 c001 = normal c002 = commas,,,in the field c003 = “enclosed” c004 =
 random ” double ” quotes c005 = commas,,, ” and double “” quotes

(I suppose I should remove the older code from the blog post and just
direct people to download the latest library code.)

• Morten

Also, further in the comments is shown how to go from blob to clob (so the posted method could be used. Credits to Christopher Beck):

  function blob_to_clob( p_lob in blob ) return clob is
     l_clob_result   clob := 'X';
     l_dest_offsset integer := 1;
     l_src_offsset  integer := 1;
     l_lang_context integer := dbms_lob.default_lang_ctx;
     l_warning      integer;
  begin
     if p_lob is not null and length(p_lob) > 0 then
        dbms_lob.converttoclob(dest_lob     => l_clob_Result,
                               src_blob     => p_lob,
                               amount       => dbms_lob.lobmaxsize,
                               dest_offset  => l_dest_offsset,
                               src_offset   => l_src_offsset,
                               blob_csid    => dbms_lob.default_csid,
                               lang_context => l_lang_context,
                               warning      => l_warning);
        if l_warning != 0 then
           dbms_output.put_line('Function blob_to_clob warning:' || l_warning);
           return null;
        end if;
        return l_clob_result;
     else
        return null;
     end if;
  exception
     when others then
        dbms_output.put_line('Function blob_to_clob error:' || SQLCODE);
        return null;
  end blob_to_clob;

You could output the columns to a global temp table, or to collections, and then do your update-logic on this. (careful with GTT and apex though. No problem as long as you’re in the same session, but if you would for example make this a second process, there is no guarantee that the same session will get used!)