For our Teiid Designer 7.6 release we introduced a couple of new ways to create new source tables in your relational models.
If you have an existing model that needs a new table, select the model and choose the "New Child > Base Table ..." context action to launch the New Relational Table Wizard dialog. This wizard contains the options necessary to construct a relational table complete with columns, unique keys and foreign key definitions.
RelationalModel.xsd schema. Launch the Import wizard and select Teiid Designer's "Designer Text File >> Source or View Models" option. Then choose the "Relational Model (XML Format)" import type.
Teiid Designer Team