Which SQL command deletes all rows from a table without deleting the structural schema, cannot be rolled back easily in some systems, and does not fire delete triggers?
Explanation:
TRUNCATE is a DDL command that quickly removes all records from a table by deallocating the data pages, bypassing row-level logging and triggers while leaving the table structure intact.
Which type of JOIN returns all matching rows from both tables, plus all unmatched rows from the left table with NULL values filled in for the right table columns?
Explanation:
A Left Outer Join preserves all records from the left table, matching them with right table records when possible, or inserting NULL values if no match is found.
Explanation:
A subquery (or nested query) is an inner SQL SELECT statement embedded within an outer statement (such as a WHERE, FROM, or SELECT clause).
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