'Smiley' in the Status Bar

The "smiley" is an indication of how valid your table is.

If he’s happy , then your table schema has been checked and is OK (within reason ‑ see below).

If he’s sad, then the table schema has been checked but there are errors.

If he’s undecided, it means that you have made some changes but haven’t yet checked the table schema.

The panel to the right of the smiley indicates whether or not you are editing the "active" table schema file (i.e. the one that SQL Direct Configuration is configured to use for the current connection). The icon in here reminds you that making changes may be dangerous.

The third icon panel indicates whether or not you have made changes to the file and have not yet saved them.