10 1Z0-071 Practice Questions Mapped to Every Oracle SQL Objective

You've read the study guide. You've watched the tutorials. But when you sit down to actually answer a question under exam conditions, something feels off.

That gap between "I understand SQL" and "I can pass the 1Z0-071" is exactly where most candidates get stuck. And it's exactly what this guide fixes.

Below are 10 carefully selected 1Z0-071 practice questions, each one mapped directly to a core objective on the Oracle Database SQL exam blueprint. Work through them honestly, and you'll know precisely where you stand before test day decides it for you.

Let's get into it.

Why Objective-Mapped Practice Actually Works

Random question dumps feel productive. They're not.

If you're not tracking which exam domain each question belongs to, you're just guessing at your own readiness. That's a risky bet when the exam fee, the scheduling hassle, and your certification timeline are all on the line.

Mapping questions to objectives changes that. It shows you exactly which areas are exam-ready and which ones need another pass. No guesswork. No surprises in the testing centre.

Here's how the ten questions break down.

1. Retrieving Data with SELECT Statements (1Z0-071) 

Question: Which clause restricts the columns returned by a SELECT statement to just the ones you need?

Answer: The column list right after SELECT, not WHERE, not FROM. This objective trips up beginners who confuse column selection with row filtering.

Get this foundation solid, because everything else builds on it.

2. Filtering Rows with WHERE

Question: What's the difference between using = and LIKE in a WHERE clause?

Answer: = demands an exact match; LIKE allows pattern matching with wildcards like % and _. Oracle loves testing this distinction with tricky wildcard combinations.

Once filtering clicks, joins are your next hurdle, and they're where real exam anxiety tends to start.

3. Joining Multiple Tables

Question: What happens when you perform an INNER JOIN versus a LEFT OUTER JOIN on two tables with unmatched rows?

Answer: INNER JOIN returns only matching rows; LEFT OUTER JOIN keeps every row from the left table, filling unmatched columns with NULL. Miss this concept, and entire question clusters become unsolvable.

Joins lead naturally into aggregation, another heavily weighted objective.

4. Aggregating Data with Group Functions

Question: Why does a query using GROUP BY fail when a non-aggregated column is included in SELECT but not in the GROUP BY clause?

Answer: Oracle enforces strict grouping rules: every non-aggregated column in SELECT must appear in GROUP BY. This is a classic 1Z0-071 gotcha.

Speaking of gotchas, subqueries are where candidates lose the most points.

5. Using Subqueries

Question: When should you use a single-row subquery versus a multiple-row subquery?

Answer: Single-row subqueries pair with =, >, <; multiple-row subqueries need IN, ANY, or ALL. Mixing these up throws a runtime error, and a wasted exam minute.

Next up: combining result sets, a smaller but still testable objective.

6. Applying Set Operators

Question: What's the key difference between UNION and UNION ALL?

Answer: UNION removes duplicate rows by sorting and comparing the combined result; UNION ALL skips that step and keeps every row, including duplicates. Because it avoids the dedup pass, UNION ALL is usually the faster option — Oracle expects you to know when performance matters more than deduplication.

Now let's shift from querying to actually shaping the database structure.

7. Creating and Managing Tables (DDL)

Question: Which command modifies an existing table's structure without deleting its data?

Answer: ALTER TABLE. Confusing this with CREATE TABLE or DROP TABLE is a common, and costly, exam mistake.

Structure means nothing without data inside it, which brings us to DML.

8. Manipulating Data with DML

Question: What is the difference between DELETE and TRUNCATE commands in deleting rows?

Answer: DELETE deletes rows individually, allows filtering with WHERE, logs the transaction, and can be undone before commit. TRUNCATE deletes all rows at once, does not allow filtering, and as DDL rather than DML, does a commit and cannot be undone. Oracle regularly checks this difference, as the most common mistake among candidates is that they think the two are equivalent.

Now that you can create and fill your tables with data, it is time to ensure the integrity of your data.

9. Enforcing Data Integrity with Constraints

Question: How is a UNIQUE constraint different from a PRIMARY KEY constraint?

Answer: Both ensure uniqueness of data, but the PRIMARY KEY also ensures no NULLs, and there can only be one per table, while the UNIQUE constraint permits a NULL value once per column (NULL is not equal to NULL), and there can be multiple UNIQUE constraints per table. The test will often assess if you understand that a table can live without a primary key, but usually shouldn’t.

Final destination objects residing above your tables, instead of storing data in them.

10. Working with Views

Question: Why might a view be non-updatable, even though it's built from a single base table?

Answer: A view becomes non-updatable if it includes group functions, GROUP BY, DISTINCT, set operators, or certain expressions in the SELECT list, since Oracle can't map the changed row back to a single unambiguous row in the base table. This objective separates candidates who memorized the syntax from those who understand what a view actually is: a stored query, not a stored table.

Where This Leaves You

Ten questions. Ten objectives. And hopefully, a much clearer picture of where your preparation actually stands.

But here's the real deal: clearing the 1Z0-071 isn't based on learning ten questions. It involves spotting patterns across dozens of scenarios like those above, within limited time, and without any safety net.

It's for this reason that real contenders go beyond a single practice set — they work systematically through the full range of Oracle certification exam questions and track their weaknesses until every domain becomes second nature.

Don't wait until you're in the exam to find your gaps. Keep practicing, and keep measuring your progress against the actual blueprint.