SQL

Interpret an entity-relationship diagram to identify the tables, columns, keys, and relationships needed by a query.

Distinguish logical relational structures from the physical storage structures used by an Oracle database.

Classify PRIMARY KEY, UNIQUE, FOREIGN KEY, NOT NULL, and CHECK constraints by the integrity rule each enforces.

Inspect a table's column names, data types, and nullability with DESCRIBE.

Apply Oracle's rules for column aliases in a SELECT result.

Predict the effect of NULL values in arithmetic expressions and comparisons.

Construct output using concatenation, character literals, and Oracle's alternative quoting syntax.

Use DISTINCT correctly to eliminate duplicate result rows.

Filter rows with comparison operators, BETWEEN, and IN.

Filter text and NULL values with LIKE, escape characters, IS NULL, and IS NOT NULL.

Evaluate compound WHERE conditions using AND, OR, NOT, and Oracle's operator precedence.

Sort query results by multiple columns, expressions, aliases, and explicit NULL placement.

Return a specified page of sorted rows with OFFSET and FETCH.

Use single-ampersand and double-ampersand substitution variables in an Oracle-compatible client.

Control reusable substitution input with DEFINE, UNDEFINE, ACCEPT, and VERIFY.

Diagnose a SELECT query whose filtering, sorting, or row-limiting behavior differs from its stated requirement.

Transform character case with UPPER, LOWER, and INITCAP.

Extract, locate, measure, replace, trim, and pad character data with Oracle character functions.

Round, truncate, and calculate remainders for numeric values with ROUND, TRUNC, and MOD.

Calculate intervals and future or past values with Oracle DATE arithmetic.

Find calendar boundaries and month relationships with MONTHS_BETWEEN, ADD_MONTHS, NEXT_DAY, and LAST_DAY.

Convert and format character, numeric, and datetime values with TO_CHAR, TO_NUMBER, and TO_DATE.

Handle NULL values with NVL, NVL2, NULLIF, and COALESCE while respecting data-type conversion rules.

Produce conditional values with searched CASE, simple CASE, and DECODE.

Predict how COUNT, SUM, AVG, MIN, and MAX treat NULL values and DISTINCT arguments.

Build grouped reports with one GROUP BY expression.

Build grouped reports using multiple grouping expressions.

Filter completed groups with HAVING.

Combine WHERE, GROUP BY, HAVING, and ORDER BY in the correct logical sequence.

Apply a group function to the result of another group function where Oracle permits nesting.

Create conditional aggregates by combining CASE expressions with group functions.

Correct ORA-00979 and related grouping errors in an aggregate query.

Retrieve matching rows with an ANSI INNER JOIN.

Join three or more tables while preserving the intended table relationships.

Build a non-equijoin for range-based relationships.

Relate rows within one table by using a self-join and distinct table aliases.

Preserve unmatched rows with LEFT, RIGHT, and FULL OUTER JOIN.

Produce and recognize Cartesian products with CROSS JOIN or a missing join condition.

Use NATURAL JOIN and JOIN USING while accounting for their column-reference restrictions.

Translate a join between ANSI syntax and Oracle's legacy join syntax, including the outer-join operator.

Use a single-row subquery with an appropriate comparison operator.

Use IN and NOT IN with a multiple-row subquery.

Compare a value with a multiple-row subquery by using ANY and ALL.

Predict and prevent NULL-related failures in NOT IN subqueries.

Write a correlated subquery that refers to a row from its outer query.

Test for related-row existence with EXISTS and NOT EXISTS.

Use a scalar subquery in a SELECT list or expression.

Combine compatible query results with UNION, UNION ALL, INTERSECT, and MINUS while observing data-type and ORDER BY rules.

Insert one row while handling column order, NULL values, defaults, and Oracle datetime literals.

Insert rows selected from another table with INSERT INTO ... SELECT.

Route source rows into multiple tables with unconditional or conditional multitable INSERT.

Update rows using values returned by a subquery.

Delete rows using a correlated condition or subquery.

Synchronize source and target data with MERGE.

Control a transaction with COMMIT, ROLLBACK, and SAVEPOINT.

Predict transaction boundaries, read consistency, and row-locking behavior, including SELECT FOR UPDATE.

Choose appropriate Oracle character, numeric, binary, and datetime data types for specified columns.

Create a table from a specification containing names, data types, defaults, and identity behavior.

Define column-level and table-level constraints with meaningful constraint names.

Implement parent-child integrity with FOREIGN KEY options such as ON DELETE CASCADE and ON DELETE SET NULL.

Create a table from query results with CREATE TABLE AS SELECT and predict what metadata is copied.

Modify columns and constraints safely with ALTER TABLE.

Distinguish DELETE, TRUNCATE, and DROP by their effects on data, structure, transactions, and dependent objects.

Create and query a temporary table or external table for a stated data-loading requirement.

Create simple and complex views and determine whether each is inherently updatable.

Control view-based changes with WITH CHECK OPTION and WITH READ ONLY.

Generate surrogate key values with sequences and explain gaps, caching, NEXTVAL, and CURRVAL.

Create an index and identify when Oracle can use it to improve data access.

Use synonyms to provide alternate names for schema objects.

Inspect objects, tables, columns, constraints, and indexes with appropriate USER_, ALL_, or DBA_ data dictionary views.

Distinguish system privileges, object privileges, and roles in an access-control scenario.

Grant and revoke object access while accounting for WITH GRANT OPTION and cascading effects.

Choose among DATE, TIMESTAMP, TIMESTAMP WITH TIME ZONE, and TIMESTAMP WITH LOCAL TIME ZONE for a stated requirement.

Compare SYSDATE, CURRENT_DATE, SYSTIMESTAMP, CURRENT_TIMESTAMP, and LOCALTIMESTAMP in database and session contexts.

Convert datetime values between named regions or offsets with FROM_TZ and AT TIME ZONE.

Solve an integrated reporting problem using joins, filtering, grouping, conditional expressions, and subqueries.

Diagnose syntax, data-type conversion, NULL-handling, and logical errors in an exam-style SQL statement.

Complete a timed set of Oracle SQL questions using an explicit strategy for eliminating incorrect options.

Classify errors from a practice set by topic and select the prerequisite skill that needs review.

Complete a timed hands-on scenario that combines schema definition, data manipulation, querying, and transaction control.