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Retrieving Image Data Types

This example retrieves images from the dbtoolboxdemo data source using a sample file that parses image data, matlabroot/toolbox/database/vqb/parsebinary.m.

  1. Connect to the dbtoolboxdemo data source.

    conn = database('dbtoolboxdemo', '', '');

    Alternatively, you can use the native ODBC interface for an ODBC connection. For details, see database.

  2. Specify cellarray as the data return format preference.

  3. Import the InvoiceNumber and Receipt columns of data from the Invoice table.

    curs = exec(conn, 'select InvoiceNumber, Receipt from Invoice')
    curs = fetch(curs);
  4. View the data you imported.

    ans = 
        [  2101]    [1948410x1 int8]
        [  3546]    [2059994x1 int8]
        [ 33116]    [ 487034x1 int8]
        [ 34155]    [2059994x1 int8]
        [ 34267]    [2454554x1 int8]
        [ 37197]    [1926362x1 int8]
        [ 37281]    [2403674x1 int8]
        [ 41011]    [1920474x1 int8]
        [ 61178]    [2378330x1 int8]
        [ 62145]    [ 492314x1 int8]
        [456789]                  []
        [987654]                  []

      Note:   Some OTHER data type fields may be empty, indicating that the data could not pass through the JDBC/ODBC bridge.

  5. Assign the image element you want to the variable receipt.

    receipt = curs.Data{1,2};
  6. Run parsebinary. This program writes the retrieved data to a file, strips ODBC header information from it, and displays receipt as a bitmap image in a figure window. Ensure that your current folder is writable so that the output of parsebinary can be written to it.

    cd 'I:\MATLABFiles\myfiles
    parsebinary(receipt, 'BMP');

    For details about parsebinary, enter help parsebinary or view its file in the MATLAB® Editor/Debugger by entering open parsebinary.

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