SQL Query plugin is one of the top-ten downloaded IntelliJ IDEA plugins. It allows executing SQL statements through a JDBC connection right from IntelliJ IDEA. It provides you with a syntax highlighting, allows you to work with multiple open queries, save and load queries, and a lot more.
The plugin also helps you to browse for database structure showing you data types, procedures, functions, tables, foreign keys, primary keys, and indexes.
The plugin is free and available through IntelliJ IDEA Plugin Manager.
To find the full description of the plugin features, either visit the SQL plugin page or see the description of the plugin at IntelliJ IDEA plugin repository.