Bill,

> Some said in old sql standard, zero-length (empty) string will be

converted to

> null, eg,

This isn't true. The SQL standard differs between NULL and ''.

> update foo set bar=''
> will effectively become
> update foo set bar=null

See above.

> Is this true for FB1.5 and FB2 ?

No, Fb follows the SQL standard. NULL and '' are different.

> A related question, in DDL, is
> a varchar(10) default ''
> equivalent to
> bar varchar(10) default null

Martijn Tonies
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