problem with Delphi 1.0 and Oracle 7.3

Delphi 1.0 => Oracle 7.3
i created a table with float fields. than i used a ttable component to edit
the table. (works perfect)
now i want to use a tquery to modify the table.
        property sql
                SELECT * FROM TB_TEST

        property requestlive

a tdbgrid shows the right values in the table, BUT now i can't write a
float value in
the table. i use the oracle driver that comes with sql links from borland,
because the
odbc driver from oracle doesn't work with my stored procedures.

HELP, what's the problem?

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