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  1. MariaDB Server
  2. MDEV-21340

stored function can see half-updated table

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      Description

      Normally if the table is being updated/deleted and selected from, execution stores rowids
      in a temp table first (used_key_is_modified, multi-update, query_plan.using_io_buffer, whatever).

      But accessing the table-to-be-updated (or deleted) from a stored function bypasses this check:

      create table t1 (i int);
      insert t1 values (1), (1);
      create function summ () returns int return (select sum(i) from t1);
      update t1 set i=summ();
      --echo # both rows should be 2
      select * from t1;
      update t1 set i=1;
      delete from t1 where i+1=summ();
      --echo # should be empty
      select * from t1;
      drop table t1;
      drop function summ;
      

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            Assignee:
            sanja Oleksandr Byelkin
            Reporter:
            serg Sergei Golubchik
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              Created:
              Updated: