When you are using SQL Server, you can define different schemas inside the database. Inside the database, you can define a table using
   schema.owner.table
i.e., you can define a table inside the database AdventureWorks, with the name
   HumanResources.dbo.EmployeeData

When i try to use a table in another schema (not the default schema), i cannot select a different schema and i cannot select the table from the list.

When i define a sql query using the table, i cannot get the table columns in the designer. In First time, the designer shows the columns, but after any interaction, the table disappear.

I am using the MS SQL Server JDBC driver and the AdventureWorks sample database installed with several MS products.