private Schema makeBaseSchema() {
Schema s = new Schema("schema");
Table t1 = s.createTable("t1");
t1.addColumn(new Column("a", new IntDataType()));
t1.addColumn(new Column("b", new IntDataType()));
t1.addColumn(new Column("c", new IntDataType()));
Table t2 = s.createTable("t2");
t2.addColumn(new Column("d", new IntDataType()));
t2.addColumn(new Column("e", new IntDataType()));
t2.addColumn(new Column("f", new IntDataType()));
Table t3 = s.createTable("t3");
t3.addColumn(new Column("g", new IntDataType()));
t3.addColumn(new Column("h", new IntDataType()));
t3.addColumn(new Column("i", new IntDataType()));
return s;
}
