Avoid Changes to the Inner Table of an Outer Join
Performance impact: Variable
Since outer join maintenance is more expensive when changes happen to
an inner table, try to avoid changes to the inner table of an outer join.
When possible, perform INSERT operations on an inner table
before inserting into the associated join rows into an outer table. Likewise, when
possible perform DELETE operations on the outer table before deleting
from the inner table. This avoids having to convert non-matching rows into matching rows
or vice versa.