How can I list all tables in a database with Squirrel SQL?

You can do it easily from the GUI. After you open your session, click the Objects tab, then expand the tree. Expand the db, schema, and then table nodes, and you'll see all of your tables. If you click on a particular table node, a table will open to the right. By clicking the Columns tab, you can get the column names, types, and other meta data.

Or are you looking for SQL commands?

Sometimes I noticed that doing the above may not result in the tables showing. Before I figured this out, my table node will not be expandable and I can never get a list of the tables.

After a lot of searching on the internet, I learnt that you need to choose the schema from the catalog drop down box located at the upper left portion of the squirrel sql client before the icons to be able to get the table list for that particular schema.

Hope that helps.