Correlated subqueries are similar to a regular subquery.

More Questions from Database Redesign

• Because of the need for extensive knowledge of SQL, many database developers choose to automate the redesign process.
• If a database is built correctly the first time, it will not have to be redesigned.
• Database redesign is especially difficult if the database has no data.
• The data model produced from the reverse engineering process is a true logical model.
• A correlated subquery is processed as a nested subquery.
• The SQL-92 command to change a table name is RENAME TABLE.
• The use of the double NOT EXISTS can be used to find rows that do not match some specified condition.

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