Referential integrity is the idea of ensuring that values linking the tables together through the primary and foreign keys are valid and correctly synchronized. * True False A crow's foot on each side of a relationship indicates a one-to-one relationship. * True O False A subquery, or nested SELECT, is a SELECT nested within another SELECT. * True False To distinguish between columns with identical names, they must by qualified by prefixing the table name. True False An associative entity is created to store data about the relationship when we have a many-to-many relationship. * True False A view does not physically exist as stored data; it is an imaginary table constructed from existing tables as required. * True False A deletion anomaly occurs when the entire primary key is not known, and the database cannot delete a record. * True False A correlated subquery is used when the inner query's execution depends on receiving a value for a variable from the outer query.* True False A non-identifying relationship is applied when the entity at the many end of the relationship is a weak entity and requires the identifier of the one end of the relationship to uniquely identify an instance of the relationship. * True If a database had four tables and you were required to join all tables, then you would be required to have four joins. * True False An update anomaly occurs when the same data are stored in more than one place in the database. * True False EXISTS is used in a WHERE clause to test whether a table contains at least one row satisfying a specified condition. * True False