Some features at a glance

• Connection parameters for individual databases are kept in a configuration file in your home directory.
• Databases can be assigned multiple logical names.
• sqlcmd has command history management, with GNU Readline support. History files are saved per database.
• sqlcmd supports SQL, but also supports database metadata (getting a list of tables, querying the table's columns and their data types, listing the indexes and foreign keys for a table, etc.).
• sqlcmd supports Unix shell-style variables.
• sqlcmd command has a .set command that displays and controls sqlcmd settings.
• sqlcmd provides a standard interface that works the same no matter what database you're using.
• sqlcmd uses the enhanced database drivers in the Grizzled API's db module. (Those drivers are, in turn, built on top of standard Python DB API drivers like psycopg2 and MySQLdb.)
• sqlcmd is written entirely in Python, which makes it very portable (though the database drivers are often written in C and may not be available on all platforms).

In short, sqlcmd is a SQL command tool that attempts to provide the same interface for all supported databases and across all platforms.