[DOCS] SELECT , UNION INTERSECT EXCEPT clause - Mailing list pgsql-docs

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Page: https://www.postgresql.org/docs/9.6/static/sql-select.html
Description:

https://www.postgresql.org/docs/current/static/sql-select.html#SQL-UNION
In  this section there is information about usage ORDER BY and LIMIT inside
second UNION subquery. In my opinion, it's necessary to add information
about the same behavior of WITH clause and FOR and FETCH clauses.