How to determine the size used in a BLOB field?

kadee
kadee Member Posts: 7
edited 2004-07-09 in Navision Attain
Does anyone know how to determine the size used in a BLOB field, in a native Navision environment?
I have been searching the Help, documentation and virtual tables, but without result :(

Comments

  • Afonso
    Afonso Member Posts: 27
    Hello,

    I think this is a limited size field, you can input files until a certain size, i don't remember the exact size, but you cannot change the size used in the BLOB.

    Regards

    Afonso
  • kine
    kine Member Posts: 12,562
    WHat about this workaround:

    export blob into file and get size of this file... :-)

    I didn't found standard function for this...
    Kamil Sacek
    MVP - Dynamics NAV
    My BLOG
    NAVERTICA a.s.
  • fb
    fb Member Posts: 246
    Here's an idea: 
    VAR
  CompanyInfo : Record 79;
  InStreamObj : InStream;
  intLen : Integer;
  intBytesRead : Integer;
  binVariable : Binary[250];

    BEGIN
  intLen := 0;
  CompanyInfo.GET;
  CompanyInfo.CALCFIELDS(Picture);
  CompanyInfo.Picture.CREATEINSTREAM(InStreamObj);
  REPEAT
    intBytesRead := InStreamObj.READ(binVariable);
    intLen += intBytesRead;
  UNTIL intBytesRead = 0;
  MESSAGE('Company Info Picture length is %1.',FORMAT(intLen));
END
  • kadee
    kadee Member Posts: 7
    I guess determination based on an export via OutStream would be the more appealing way to choose here; too bad it can't be used for intensive operations with big files.
    Anyway, thanks for the replies, folks.
  • fb
    fb Member Posts: 246
    I'm not sure why you say 'export' and 'OutStream'. My recommendation does not require a BLOB.Export to a file, nor does it use an OutStream object.

    The 'InStream' I suggested is used as a way to 'stream the contents of the BLOB field into a local variable', counting the bytes along the way. No external file is created.

    It seems that this method should work acceptably, even with large BLOB's, no?

Categories