Are postgresql transaction levels repeatable for reading and serializing?

Question

Quote from http://www.postgresql.org/docs/9.4/static/transaction-iso.html :

When you select the Read Uncommitted level, you really get Read Committed, and phantom reading is not possible in the PostgreSQL implementation to read again, so the actual isolation level may be more severe than what you choose.

To clarify: does this mean pg repeatable read = serializable?

Answer 1

No; the difference is described on the page with which you are connected :

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, PostgreSQL 9.1 . 9.0 :

, Read Committed Serializable.

:

, Read Committed, Repeatable Read Serializable.

Answer 2

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