PostgisDialect与PostgreSQLDialect或两者兼而有之？

PostgisDialect实际上扩展了Postgresql方言，所以，它是一个超集。请参阅类声明： PostgisDialect类声明

这里有一个很好的教程： Hibernate spatial with Postgis ，这表明您只需要包含Postgis Dialect就可以保留空间和非空间字段。

Postgis主要为Postgresql之上的空间对象提供支持。 Postgis安装还包括提供许多实际几何功能的GEOS（Java拓扑套件的C ++端口），Proj4，它提供对不同坐标系/投影和GDAL的支持，GDAL是各种地理数据格式之间的转换工具。 / p>

My application is going to use the following technologies:

• Postgresql
• Postgis
• JPA/Hibernate
• Spring
• Spring Data JPA

I understand (from the Hibernate Spatial documentation) that one has to use the following dialect: org.hibernate.spatial.dialect.postgis.PostgisDialect

What I don't understand though is how the above dialect relates to the standard Posgresql dialect, i.e. org.hibernate.dialect.PostgreSQLDialect...

Is the Postgis dialect a superset of the standard Posgresql dialect?

Will all features of the latest standard Posgresql dialect be available in the Postgis dialect?

I guess I can't use several/multiple dialects on the same entityManager factory... Then what are the best practices to get the best of both dialects?

The PostgisDialect actually extends the Postgresql dialect, so, yes, it is a superset. See the class declaration: PostgisDialect class declaration

There is a good tutorial here: Hibernate spatial with Postgis that show that you only need to include the Postgis Dialect in order to persist both spatial and non-spatial fields.

Postgis primary provides support for spatial objects on top of Postgresql. A Postgis installation also includes GEOS (a C++ port of Java Topology Suite) which provides many of the actual geometric functions, Proj4, which provides support for different coordinate systems/projections and GDAL, which is a conversion utility between various geographical data formats.