ADO.net: 3 Data Set Questions (Issues)

From: Mr. B (User_at_NoWhere.com)
Date: 06/26/04

  • Next message: Earl: "Re: ADO.net: 3 Data Set Questions (Issues)" 
    Date: Sat, 26 Jun 2004 19:33:04 GMT

    I'm updating my current VB.et application. I currently reads about 6 tables
    from an MS Data base. I've created a new MDB file which combines the 6 tables
    into 1 table. I'm doing this because I know I'll speed up my application
    loading time by more than 10 seconds (out of about 20).

    I've run across three situations in which I'm stuck at:

    Issue One:

    If my largest Column has (say) 200 lines, other columns will have less data
    lines. So say Column 1 has 50 lines of data, column 2 has 200 lines and
    column 3 has 150 lines. Then column 1 and 3 will have lines containing
    nothing (ie null or blank lines).

    How to I test for a 'null' in a FOR statement? This is so that I can tell
    when I've hit the end of my data for that column?

    Issue Two:

    For the above, How can I get rid of any blank lines when I bind the Datasource
    to a ComboBox pull down? Column 3 will have 50 lines of blank. So if I sort
    a ComboBox, the first 50 lines are blank! :(

    Issue Three:

    I've several ComboBox pulldowns which are bind to the same data set. But if I
    change one, then the all change! How can I control them independantly?

    For example, if I have 6 ComboBoxes. They are all bound to the same Data
    Source, but each one is bound to a different Member of that Data Source.

    So say I want to have 1 and 2 related (one changes, so does the other)... then
    3 and 4 paired together similar as 1 and 2, and 5 and 6 completely independant
    from all the others?

    Mucho Appreciated!

    Bruce

  • Next message: Earl: "Re: ADO.net: 3 Data Set Questions (Issues)"

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