[Q] Conditional Grant ?

Dear netters:

   Is it possible for ORACLE to do "run time grant" ( row level grant ?) ?

   For example:

      table         : tb1
      related column: id
      I want let "user1" manipulate those data in tb1 with tb1.id='1'.

   I guess the statement would look like:

   grant select, insert, update, delete on tb1 to user1 WHERE id='1';

   How can I do it ? ( I don't have ORACLE SQL SYNTAX REFERENCE at hand.)    Any response to answer the question is appreciated.

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Fu-Xiong Lin