When we write to a materialized view, we need to know some information
defined in the base table such as the columns in its schema. We have
a "view_info" object that tracks each view and its base.
This view_info object has a couple of mutable attributes which are
used to lazily-calculate and cache the SELECT statement needed to
read from the base table. If the base-table schema ever changes -
and the code calls set_base_info() at that point - we need to forget
this cached statement. If we don't (as before this patch), the SELECT
will use the wrong schema and writes will no longer work.
This patch also includes a reproducing test that failed before this
patch, and passes afterwords. The test creates a base table with a
view that has a non-trivial SELECT (it has a filter on one of the
base-regular columns), makes a benign modification to the base table
(just a silly addition of a comment), and then tries to write to the
view - and before this patch it fails.
Fixes#10026Fixes#11542
(cherry picked from commit 2f2f01b045)
eebe77b5b8