GUI client

I am looking for a GUI client for our PostgreSQL database. This database was designed to support the inventory of paleontological collections, and is full of fk, codelists, enumerations and triggers to ensure data consistency.

Now the problem is to have our staff entering data as they go through the inventory effort. 

Therefore I am looking for a nice GUI client that spares the users from learning SQL and that provides a nice interface for entering data. This means for example having a system that allows to pick values from an enumeration or from the table whose PK is acting as FK in the table currently being edited.

Any suggestions?

Kind Regards,

Andre

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