SASqlConsole is a unified SQL console based on SQLAlchemy. It features pretty colors, intelligent formatting of output, convenient CSV output, a consistent interface across all backends supported by SQLAlchemy, persistent readline history, and tab completion of all tables and columns and a selection of SQL keywords.
Uhura is a Web console for databases. It works with MySQL, PostgreSQL, and FirebirdSQL. It presents trees that let you browse databases, tables, columns, constraints, triggers, views, and procs. It has panels for history and fragments. Its editor features autocompletion and autoindenting. It is easy to install.