The Execute command executes all the SQL statements that are currently in the active window of the SQL Editor. You can customize the behaviour of the Execute command in Properties window of the active SQL Editor options.
The Stop Retrieval command stops the retrieval of database data. The data that has been retrieved so far is displayed in the Result tab. Use the Retrieve next n rows button or the Retrieve outstanding rows button, respectively, or the context menu in the Result view to resume retrieval. This button replaces the Execute button while data is being retrieved.