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Thread: do you know how to check if a record exist in qt ?..

  1. #1

    Default do you know how to check if a record exist in qt ?..

    do you know how to check if a record exist in qt ?..

    what i would like to do is .. i listing all the members in a drop box which the names are from across 2 database tables ...

    so i would like to check if this record exist in the first table .. else check in table 2.. then proceed to do something..

    but i am stuck on how to check if a record exist in qt.. i am using sqlite.

  2. #2
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    Default Re: do you know how to check if a record exist in qt ?..

    You execute a query looking for the record and see if it returns any rows. There is nothing Qt-specific about this.
    Qt Code:
    1. bool ok;
    2. bool foundBoth = false;
    3. ok = q.exec("select 1 from table1 where field = value");
    4. if (ok && q.next()) {
    5. ok = q.exec("select 1 from table2 where field = value");
    6. if (ok && q.next()) {
    7. foundBoth = true;
    8. }
    9. }
    To copy to clipboard, switch view to plain text mode 
    Use bound parameters if there is any chance the value can be supplied directly by the user or contain semicolons, quotes etc. Heck, just use bound parameters anyway.

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