Oracle SQL Developer is an Integrated development environment (IDE) for working with SQL in Oracle databases. Oracle Corporation provides this product free; it uses the Java Development Kit.
Oracle SQL Developer supports Oracle products. In the past a variety of third-party plugins were supported which users were able to deploy to connect to non-Oracle databases. Oracle SQL Developer worked with IBM Db2, Microsoft Access, Microsoft SQL Server, MySQL, Sybase Adaptive Server, Amazon Redshift and Teradata databases.[4]
Oracle SQL Developer supports automatic tabs, code insight, bracket matching and syntax coloring for PL/SQL.
Future versions of Oracle SQL Developer will use Visual Studio Code.[1]
Oracle SQL Developer product components include the OWA (Oracle Web Agent or MOD_PLSQL), an extension module for the Apache web server, and helps in setting up dynamic web-pages from PL/SQL within Oracle SQL Developer.[5]
In addition to the extensions provided by Oracle, third parties have written extensions to add new features to SQL Developer and to integrate with other products:[6]
OWA (Oracle Web Agent) or MOD_PLSQL is an Apache (Web Server) extension module.
SQL Developer Data Modeler is a data modeling and database design tool that provides an environment for capturing, modeling, managing, and exploiting metadata.[...] SQL Developer Data Modeler is a for-cost option of SQL Developer that requires a separate license. However, a free viewer (read-only) version is also available [...]
Is Oracle SQL Developer Data Modeler free? - Yes.
When you save a database design, the structural information is stored in an XML file (with the extension .dmd)