Query vs. DML vs DDL

[manticore-projects]

Greetings.

At the moment all Statements just extend Statement and we do not know if the Statement is a Query, a DML or a DDL (unless we test a lot of instance of).

I would like to suggest to
a) either introduce new Abstract Classes QueryStatement, DmlStatement' and DdlStatementuse these (instead ofStatement) for implementing each Statement b) or to declare Statementabstract with additional methodsgetStatementType()(returningQuery, DDLorDML) and isQuery(), isDml()andisDdl()`

Which way would be preferred? I tended to option a).

[wumpz]

Wouldn't it be sufficient to introduce some kind of grouping interfaces? What should be within the abstract base clases?

[manticore-projects]

Quick and dirty draft for discussion:

public abstract class StatementImpl implements Statement {
    abstract StringBuilder appendTo(StringBuilder builder);
    
    @Override
    public String toString() {
        return appendTo(new StringBuilder()).toString();
    }
}

public abstract class DDLStatement extends StatementImpl {

}

public abstract class DMLStatement extends StatementImpl {

}

public abstract class QueryStatement extends StatementImpl {

}

And then every Statement class should extend one of these, like:

public class Select extends QueryStatement {
....
}

public class Insert extends DMLStatement {
....
}

[manticore-projects]

Solved via PR #1301