1. 大师：
Virtuoso 是一种中间件，支持管理表示为关系表和/或属性图的数据。它是一个多模型混合 RDBMS，其中包含主要数据库模型，如图形 DBMS、本机 XML DBMS、关系 DBMS、RDF 存储、搜索引擎。它旨在利用操作系统线程支持和多个 CPU。 Virtuoso 对象关系数据库 (ORDBMS) 支持实体完整性和参照完整性。
1. XAP：
XAP用于关键任务应用程序的高性能内存数据网格，并提供一组基本的数据存储功能，例如事务、索引和查询语言(类 SQL 查询)。它是一种用于安装和分发应用软件的文件格式。
XAP 和 Virtuoso 的区别：
| S.No. | XAP | Virtuoso |
|---|---|---|
| 1 | Developed by Gigaspaces Technologies and initially released on 2000 and current release on June 2019. | Developed by Virtuoso and initially released on 1998 and current release on May 2019. |
| 2 | Its primary database model is Document store and Key-value store. | Its primary database model is Graph DBMS, Native XML DBMS, Relational DBMS, RDF store, Search engine. |
| 3 | Its secondary database models is Object oriented DBMS. | Its secondary database models is Document store. |
| 4 | Server operating systems of XAP Linux, macOS, Solaris, Windows. | Server operating systems of AIX, FreeBSD, HP-UX, Linux, OS X, Solaris, Windows. |
| 5 | XAP supports GigaSpaces LRMI, Hibernate, JCache, JDBC, JPA, ODBC, RESTful HTTP API, Spring Data. | Virtuoso supports ADO.NET, GeoSPARQL, HTTP API, JDBC, Jena, RDF API, ODBC, OLE DB, RDF4J API, RESTful HTTP API, Sesame REST HTTP Protocol, SOAP, webservices, WebDAV, XPath, XQuery, XSLT. |
| 6 | XAP has ACID (Atomicity, Consistency, Isolation, and Durability) concepts transaction concepts. | Its Transaction concepts is ACID (Atomicity, Consistency, Isolation, and Durability). |
| 7 | Replication methods of XAP- Master-master replication and Master-slave replication. | Replication methods of Virtuoso is based on Chain, star, and bi-directional replication, Master-master replication, Master-slave replication. |
| 8 | Partitioning methods of XAP is Sharding. | It doesn’t holds sharding partitioning methods. |
| 9 | XAP supports .Net, C++, Java programming languages. | Virtuoso supports .Net, C, C#, C++, Java, JavaScript, Perl, PHP, Python, Ruby, Visual Basic programming languages. |
| 10 | It has Immediate Consistency concept. | Yes, Virtuoso has Consistency concept. |
| 11 | Implementation language of XAP is Java, C++, .Net. | Implementation language of Virtuoso is C. |
| 12 | It doesn’t holds Foreign keys. | It holds Foreign keys. |
| 13 | It has SQL-like query language and DML statements. | Yes, Virtuoso has SQL. |