Please try renaming your database to use all lower-case letters. The lower-case naming convention is suggested by PostgreSQL, and should resolve the error you are seeing in MATLAB.
This error is due to a difference in naming conventions between SQL and PostgreSQL.
According to PostgreSQL's standards, any unquoted names in queries are converted to lower-case letters, so when myDB is a part of the query, PostgreSQL interprets it as mydb instead. Since Database Explorer prepends the database name and schema name to the table name, and since the database name is not all lowercase, PostgreSQL interprets Database Explorer's query for myDB.public.person as mydb.public.person. This raises an error because you are connected to myDB but PostgreSQL thinks you are trying to query mydb, which it interprets as a different database.
The way to enforce capitalization in PostgreSQL and SQL is to surround each case-sensitive name in quotes. For example, if you change the query from
SELECT * FROM myDB.public.person
to
SELECT * FROM "myDB".public.cats
The query should be successful.
Note that this forcing to lower-case is a PostgreSQL-specific behavior. Database Explorer is generally agnostic to the type of database being used, so this behavior is not being accounted for.
You can read more about this behavior in the PostgreSQL documentation:
The relevant section is 4.1.1, particularly the last paragraph.
Best Answer