1Z0-006 Cheat Sheet 2026

The 30 highest-yield 1Z0-006 facts, distilled from real exam questions. Print it, save it as a PDF, or study it here — free, no sign-up.

1. In relational database terminology, what is a 'tuple'? → A row in a table
2. Which function returns the number of rows in a group or entire table? → COUNT()
3. What is the purpose of Oracle's FLASHBACK DATABASE feature? → To rewind the entire database to a previous point in time
4. Which function returns the number of non-NULL values in a column? → COUNT(column)
5. Which clause is required in every valid SELECT statement in Oracle? → FROM
6. In a relational database, what is a candidate key? → Any minimal set of attributes that can uniquely identify a row
7. Which SELECT clause is evaluated FIRST by the Oracle SQL engine during query processing? → FROM
8. What is the purpose of the Oracle recycle bin? → Retains dropped tables and their objects so they can be recovered with FLASHBACK TABLE
9. What is the purpose of the SPFILE (Server Parameter File) in Oracle? → Stores database initialization parameters persistently in binary format on the server
10. What does DDL stand for in the context of SQL? → Data Definition Language
11. What happens when you execute DELETE FROM orders; with no WHERE clause? → All rows in the orders table are deleted but the table structure remains
12. Which concept ensures that every row in a table can be uniquely identified? → Primary key
13. When an ER diagram shows a relationship with an attribute (e.g., 'Date' on a WORKS_FOR relationship), what does this indicate? → The attribute describes a property of the relationship itself, not either entity alone
14. Which background process writes redo entries from the Redo Log Buffer to the online redo log files? → LGWR
15. Which SQL set operator returns only the rows that appear in both result sets? → INTERSECT
16. Which type of Oracle backup captures only the data blocks changed since the last backup? → Incremental backup
17. Which Oracle feature provides row-level security by automatically appending a WHERE clause to queries on a table? → Virtual Private Database (VPD)
18. Which SQL function concatenates two strings in Oracle? → CONCAT(str1, str2) or str1 || str2
19. Which relational model concept states that every row in a table must be uniquely identifiable? → Entity integrity
20. The principle of least privilege suggests that users should: → Receive only necessary privileges
21. Which operator tests whether a value falls within an inclusive range in a WHERE clause? → BETWEEN low AND high
22. In Oracle, which dictionary view would you query to see the privileges granted directly to a specific user (not through roles)? → DBA_SYS_PRIVS
23. Which automatic feature in Oracle attempts to protect against SQL injection by verifying input types? → DBMS_ASSERT
24. In data modeling, what does 'domain' refer to? → The set of all valid values an attribute can hold
25. What does the DISTINCT keyword do in a SELECT statement? → Removes duplicate rows from the result set
26. Which SGA component stores the most recently executed SQL statements and their execution plans? → Shared pool
27. In the context of the relational data model, what is the primary purpose of normalization? → To reduce data redundancy and improve data integrity.
28. Which SELECT statement retrieves distinct department IDs from the employees table? → SELECT DISTINCT department_id FROM employees;
29. What is the purpose of the ROLLBACK command in SQL? → To undo all changes made since the last COMMIT
30. Which SQL function converts a string to uppercase? → UPPER