It is one of the important goals of MetaModel to be compliant with as many databases and datastores as possible! We ensure a broad compliance by several initiatives:
| Database | Version | JDBC driver | Compliancy |
| MySQL | 5+ | Connector/J | Fully compliant |
| PostgreSQL | 8+ | PostgreSQL JDBC driver | Fully compliant |
| Oracle | 10g | SQLJ/JDBC | Fully compliant |
| Apache Derby | 10+ | Derby driver | Fully compliant |
| Firebird SQL | 2.0+ | Jaybird driver | Fully compliant |
| Hsqldb/HyperSQL | 1.8+ | Hsqldb driver | Fully compliant |
| H2 | 1.2+ | H2 driver | Fully compliant |
| SQLite | 3.6.0+ | Xerial driver | Fully compliant |
| Microsoft SQL Server | 2005 (+ possibly others) | JTDS driver | Fully compliant |
| Ingres | - | Ingres JDBC driver | Fully compliant |
| File format | File extension | Version | Compliancy |
| Comma separated file | .csv | - | Fully compliant |
| Microsoft Excel spreadsheet | .xls | Excel '97-2003 | Fully compliant |
| .xlsx | Excel 2007+ | Fully compliant | |
| OpenOffice.org database | .odb | OpenOffice 2.0+ | Fully compliant |
| XML file (SAX based) | .xml | - | Fully compliant |
| XML file (DOM based) | .xml | - | Experimental |
| Microsoft Access database | .mdb | Access '97-2003 | Fully compliant |
| .accdb | Access 2007+ | Fully compliant | |
| dBase database | .dbf | - | Fully compliant |
MetaModel supports an advanced feature called composite datastores. In short it means that it's possible to access and query several datastores as if they where one. This involves transparent client-side joining, filtering, grouping etc. Composite datastores are typically not as performant in terms of querying but provides for a convenient way to combine data that is otherwise inherently separated from each other.