After upgrading from 7.1 to 8.0 and I've noticed a change in the Insert/Update step. An empty string gets set to a NULL value in the target database instead of an empty string. Version 7.1 did not do this.
Can you please provide more detailed reproduction steps? I've tested in Pentaho versions 7.1 and 8.0 inserting an empty string into both PostgreSQL and MySQL databases using the Insert/Update step and every time the empty string is inserted as a NULL value.
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