how to import specific cell(s) from table of database to Matlab?

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MatlabFan 2013-4-7

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https://ww2.mathworks.cn/matlabcentral/answers/70401-how-to-import-specific-cell-s-from-table-of-database-to-matlab

Hi,

I have the database toolbox, and I am trying to import the information that is contained in specific cells of a table from the database to Matlab. I have tried several things, among others:

 if true
    %  conn = database('myfirstsource', '', '');
  setdbprefs('DataReturnFormat','cellarray');
    curs = exec(conn, 'select * from userPassword');
    columnnames(curs);
    entries=curs.Data(:,1)
  end

But it does not work. what i have returned is:

curs =

        Attributes: []
              Data: 0
    DatabaseObject: [1x1 database]
          RowLimit: 0
          SQLQuery: 'select * from userPassword'
           Message: []
              Type: 'Database Cursor Object'
         ResultSet: [1x1 sun.jdbc.odbc.JdbcOdbcResultSet]
            Cursor: [1x1 com.mathworks.toolbox.database.sqlExec]
         Statement: [1x1 sun.jdbc.odbc.JdbcOdbcStatement]
             Fetch: 0

ans =

[]

entries =

below is what is the link to the table in the database. <http://tinypic.com/r/5obb5f/6>

Why is the above code not returning the cells in the table? What am I missing?

Please help.

Thank you.

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MatlabFan 2013-4-7

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I figured it out. I needed to place a fetch statement after the execution statement. That is, right after the exec statement, i needed to write:

curs=fetch(curs)

That problem is solved.

Now, I would like to update the content of a specific cell in a table in the database. I tried using:

     colnames={'Password'};
     exdata='NewPassword';
     fileSelected='BobSpreadsheet.xlsx';
 update(conn, 'userPassword', colnames, exdata, ...
     'where Username =', fileSelected)

The problem is that instead of updating the password where Username = BobSpreadsheet.xlsx, it creates a new row with Username= BobSpreadsheet.xlsx and Password=NewPassword.

How do I update the password for BobSpreadsheet.xlsx without creating a new row ?

Any idea is welcome.

Thanks.

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