Selecting from analytical tables.

For these operations, standard Postgres Pro views are used. Currently, reading a view associated with an analytical table returns the latest version of data, even for transactions with the repeatable read isolation level or higher. In this case, only committed OLAP data is visible.

Storage mechanisms are used to provide isolation.

Other ETL operations with pgpro_metastore.

During the execution of these procedures, read-only queries are sent to pgpro_metastore, and all queries updating metadata are executed at the end in a single serialized transaction. This allows resolving most of the conflicts. The additional triggers logic is used when required.

For more information, refer to Chapter 15, Chapter 16, Chapter 19, and Chapter 20.