PostgreSQL & MySQL Database Interview Questions 2026 (Performance Tuning PDF)

Q1. What is Oracle Fusion Cloud Enterprise Structure and its core hierarchy?

Foundation • 0-2 Yrs

The Oracle Fusion hierarchy consists of: Enterprise (highest level) -> Division -> Legal Entity (registered legal company) -> Business Unit (operational unit managing AP, AR, Procurement) -> Reference Data Sets -> Inventory Organizations -> Subinventories.

Q2. What is the difference between a Legal Entity and a Business Unit in Oracle Fusion?

Foundation • 0-2 Yrs

A Legal Entity is a recognized legal company registered with government authorities capable of owning assets, entering into contracts, and filing taxes. A Business Unit performs operational business transactions (invoicing, purchasing) and is assigned to a primary ledger and legal entity.

Q3. Explain the 4 Cs of an Accounting Configuration (Primary Ledger) in Oracle Financials.

Foundation • 0-2 Yrs

Every Primary Ledger requires the 4 Cs: 1. Chart of Accounts (accounting segments); 2. Calendar (accounting period structure); 3. Currency (base functional currency); 4. Accounting Convention (Subledger Accounting rules: accrual, cash).

Q4. What is HCM Data Loader (HDL) and what file formats does it support?

Foundation • 0-2 Yrs

HDL is Oracle Cloud HCM's primary tool for bulk data migration and automated integrations. It processes pipe-delimited text files (.dat) compressed into zip archives, supporting full lifecycle records (Worker, Job, Department, Salary) with multi-threading and audit rollbacks.

Q5. What is the difference between HDL and HSDL (HCM Spreadsheet Data Loader)?

Foundation • 0-2 Yrs

HDL is designed for high-volume technical data loads via pipe-delimited .dat files and automated web service integrations. HSDL is an end-user friendly Excel spreadsheet interface (using Oracle ADF Desktop Integration) used by HR analysts for smaller, manual routine data entries.

Q6. What are Fast Formulas in Oracle Fusion HCM and where are they used?

Foundation • 0-2 Yrs

Fast Formulas are configurable business logic scripts written in English-like pseudo-language. Used in: Global Payroll (earnings, deductions calculation), Absence Management (accrual plans, carryover validation), Benefits eligibility, and Time & Labor calculations.

Q7. Explain the difference between Position Management and Job Management in Core HR.

Foundation • 0-2 Yrs

Jobs represent broad functional roles independent of headcounts (e.g., Software Engineer), defining general competencies. Positions are specific, headcount-tracked instances of a job within a specific department/location (e.g., Lead Java Engineer - Noida Pod #4), tracking vacant vs occupied seats.

Q8. What is Subledger Accounting (SLA) in Oracle Fusion Financials?

Foundation • 0-2 Yrs

SLA is the rule-based accounting engine that sits between subledger applications (Payables, Receivables, Fixed Assets) and General Ledger. It derives accounting entries (Debits/Credits, GL account segments) based on configurable Account Rules and Mapping Sets.

Q9. Explain the Procure-to-Pay (P2P) lifecycle in Oracle Fusion Cloud.

Foundation • 0-2 Yrs

Purchase Requisition -> Purchase Order (Procurement) -> Advance Shipment Notice -> Goods Receipt -> AP Invoice Entry (matching 2-way, 3-way, or 4-way) -> Payment Processing (Payment Process Request PPR) -> General Ledger posting.

Q10. What are the different Invoice Match types (2-way, 3-way, 4-way) in Oracle Payables?

Foundation • 0-2 Yrs

2-Way Matching: Matches Invoice price and quantity against Purchase Order. 3-Way Matching: Matches Invoice against PO and Goods Receipt quantity. 4-Way Matching: Matches Invoice against PO, Goods Receipt, and Quality Inspection acceptance.

Q11. What is BI Publisher (Oracle Analytics Publisher) in Oracle Fusion?

Foundation • 0-2 Yrs

BI Publisher is the enterprise pixel-perfect reporting tool in Oracle Fusion Cloud. It extracts data using SQL data models querying underlying Fusion database tables and formats outputs (PDF, Excel, Word) using RTF or XSL-FO templates.

Q12. What is an OTBI (Oracle Transactional Business Intelligence) Analysis?

Foundation • 0-2 Yrs

OTBI is a real-time ad-hoc reporting tool using pre-built Subject Areas (Logical Models). Business users drag-and-drop attributes and measures without writing raw SQL queries, running directly against transaction databases.

Q13. Explain the difference between Person, Worker, and Assignment in Oracle HCM.

Foundation • 0-2 Yrs

Person represents biographical identity (Name, National ID, DOB). Worker represents an active working relationship (Employee, Contingent Worker). Assignment stores job-specific contractual details (Department, Job, Grade, Manager, Location).

Q14. What is an Approval Management Engine (BPM / AMX) in Oracle Fusion?

Foundation • 0-2 Yrs

Oracle Fusion uses Business Process Management (BPM) Worklist and Approval Management Extensions (AMX) to define rule-based approval workflows (Supervisory hierarchy, Job levels, Approval Groups) for HR requests, invoices, and purchase requisitions.

Q15. What are Flexfields in Oracle Fusion Cloud and what types exist?

Foundation • 0-2 Yrs

Flexfields provide extensible database fields without programming: Descriptive Flexfields (DFF: additional user attributes), Extensible Flexfields (EFF: multi-row or complex hierarchical data), and Key Flexfields (KFF: core enterprise structures like Chart of Accounts).

Q16. How do you troubleshoot HDL import and load failures in Oracle Fusion HCM?

Experienced • 3-5+ Yrs

In Data Exchange -> View Business Objects, review Import status and Load status. Inspect error messages in the Diagnostic Log. Common issues include: missing foreign key references, date-effective sequence conflicts, invalid GUIDs/SourceKeys, and unmapped mandatory attributes.

Q17. Explain Date Effectivity in Oracle Fusion HCM (Correction vs Update).

Experienced • 3-5+ Yrs

Date Effectivity tracks historical changes over time without overwriting past data. 'Update' creates a new dated record starting from the specified effective date, preserving prior history. 'Correction' edits the existing record in-place across that specific date range, repairing data entry errors.

Q18. How do you write and compile an Absence Accrual Fast Formula?

Experienced • 3-5+ Yrs

Fast Formulas declare Inputs (IV_START_DATE, IV_END_DATE), fetch DB items (PER_ASG_REL_DATE_START), evaluate business logic (e.g., tenure-based accrual rate), and return output variables (ACCRUAL = calculated_val). Compiled via 'Fast Formulas' task to generate executable p-code.

Q19. Explain the role of Mapping Sets and Account Rules in Subledger Accounting (SLA).

Experienced • 3-5+ Yrs

Account Rules determine how individual Chart of Accounts segment values are derived. When segment derivation depends on input transaction values (e.g., Expense Category -> Cost Center), a Mapping Set maps source input values to target GL account segment values.

Q20. How does Oracle Integration Cloud (OIC) connect third-party systems to Fusion Cloud?

Experienced • 3-5+ Yrs

OIC uses pre-built Oracle ERP Cloud and HCM Cloud Adapters to trigger events (Business Events), invoke SOAP/REST APIs, execute bulk data synchronization via HDL/FBDI, transform payloads using XSLT, and handle bidirectional integration flows with on-premise systems.

Q21. Explain File-Based Data Import (FBDI) in Oracle Fusion Financials.

Experienced • 3-5+ Yrs

FBDI loads high-volume financial data (Journal Entries, Invoices, Customers). The process: 1. Populate standard Excel macro template; 2. Generate zip archive containing CSV; 3. Upload to UCM; 4. Run 'Load Interface File for Import'; 5. Run module import program (e.g., Import Payables Invoices).

Q22. What is the difference between a Primary Ledger, Secondary Ledger, and Reporting Currency?

Experienced • 3-5+ Yrs

Primary Ledger: Main accounting book with 4 Cs. Secondary Ledger: Parallel accounting book with different COA, calendar, or accounting convention (IFRS/Local GAAP). Reporting Currency: Same COA and calendar as primary ledger, differing only in currency for financial translation.

Q23. Explain Cross-Validation Rules (CVRs) in General Ledger.

Experienced • 3-5+ Yrs

CVRs prevent users from creating invalid accounting code combinations during transaction entry (e.g., preventing a Balance Sheet account from being combined with an Operations Cost Center), enforcing Chart of Accounts governance before journals are posted.

Q24. How do you implement Dynamic Document Approvals based on Supervisory Hierarchy in BPM?

Experienced • 3-5+ Yrs

In BPM Worklist -> Task Configuration, configure stage rules using the 'Supervisory' list builder, specifying starting approver (e.g., Requestor's Manager) and top approval condition (e.g., Level = 3 or Approval limit > $50,000).

Q25. What is Auto-Invoicing in Oracle Fusion Receivables?

Experienced • 3-5+ Yrs

AutoInvoice is the automated engine that imports invoices, debit memos, and credit memos from external billing engines or Oracle Order Management into AR, validating customers, payment terms, tax codes, and revenue accounting.

Q26. How does Global Payroll calculate Gross-to-Net in Oracle Fusion?

Experienced • 3-5+ Yrs

1. Fetch payroll relationship and element entries -> 2. Run Fast Formulas for Earnings -> 3. Calculate Statutory Tax Deductions -> 4. Calculate Voluntary Deductions -> 5. Net Pay = Gross Earnings - Total Deductions -> 6. Generate payment files and SLA journal entries.

Q27. Explain Value Sets in Oracle Fusion and their validation types.

Experienced • 3-5+ Yrs

Value Sets define permitted values for Flexfield segments. Types: Format Only, Independent (list of discrete values), Dependent (values depend on another independent segment), Table-Validated (values dynamically queried from a database table), and Subset.

Q28. How do you optimize slow BI Publisher SQL data models in Fusion Cloud?

Experienced • 3-5+ Yrs

1. Avoid SELECT *; 2. Ensure joins use indexed columns (e.g., PERSON_ID, ASSIGNMENT_ID); 3. Filter on DATE_EFFECTIVE ranges; 4. Avoid outer joins where inner joins suffice; 5. Use bind parameters instead of literal concatenation.

Q29. What are Lookups in Oracle Fusion Cloud and how do they differ from Value Sets?

Experienced • 3-5+ Yrs

Lookups are static lists of code-meaning pairs used for system drop-down menus (Common Lookups, Set-Enabled Lookups). Value Sets are used specifically within Key and Descriptive Flexfields to validate accounting segments and user-defined attributes.

Q30. Explain Cash Positioning and Bank Reconciliation in Oracle Cash Management.

Experienced • 3-5+ Yrs

Cash Management imports electronic bank statements (MT940, BAI2, CAMT.053) and performs automated reconciliation against Payables payment records and Receivables receipts based on transaction references and amounts.

Q31. Write an HDL .dat file snippet to insert a new Department.

Live Coding Challenge

We define METADATA and MERGE lines for Department business object.

METADATA|Department|DepartmentId|EffectiveStartDate|EffectiveEndDate|Name|SetCode
MERGE|Department||2026/01/01|4712/12/31|Enterprise AI Solutions|COMMON

Q32. Write a Fast Formula snippet in Oracle HCM to calculate a 10% performance bonus.

Live Coding Challenge

We declare inputs, compute percentage, and return the calculated bonus amount.

DEFAULT FOR ASG_SALARY IS 0
INPUTS ARE ASG_SALARY

BONUS_AMOUNT = ASG_SALARY * 0.10
RETURN BONUS_AMOUNT

Q33. Write a BI Publisher SQL query to fetch Employee Name, Email, and Department.

Live Coding Challenge

Query PER_ALL_PEOPLE_F, PER_EMAIL_ADDRESSES, and PER_DEPARTMENTS.

SELECT 
    ppnf.display_name,
    pea.email_address,
    pd.name as department_name
FROM per_all_people_f papf
JOIN per_person_names_f ppnf 
    ON papf.person_id = ppnf.person_id 
    AND ppnf.name_type = 'GLOBAL'
LEFT JOIN per_email_addresses pea 
    ON papf.person_id = pea.person_id 
    AND pea.email_type = 'W1'
LEFT JOIN per_all_assignments_m paam 
    ON papf.person_id = paam.person_id 
    AND paam.primary_flag = 'Y'
LEFT JOIN per_departments pd 
    ON paam.organization_id = pd.organization_id
WHERE TRUNC(SYSDATE) BETWEEN papf.effective_start_date AND papf.effective_end_date;

Q34. Write an HDL snippet to update an Employee's Job Assignment.

Live Coding Challenge

Using MERGE on Assignment component with Date-Effective start date.

METADATA|Assignment|AssignmentId|EffectiveStartDate|EffectiveEndDate|ActionCode|JobCode
MERGE|Assignment|300000012345678|2026/02/01|4712/12/31|PROMOTION|SR_DEV_JOB

Q35. Write the SQL to check GL Journal Header and Line details in Oracle Financials.

Live Coding Challenge

Query GL_JE_BATCHES, GL_JE_HEADERS, and GL_JE_LINES.

SELECT 
    jh.je_header_id,
    jh.name AS journal_name,
    jh.ledger_id,
    jl.je_line_num,
    jl.entered_dr,
    jl.entered_cr
FROM gl_je_headers jh
JOIN gl_je_lines jl ON jh.je_header_id = jl.je_header_id
WHERE jh.period_name = 'Oct-26';

Q36. Write an HDL snippet to create a Work Relationship for a new hire.

Live Coding Challenge

Define WorkRelationship component linking Person to Legal Employer.

METADATA|WorkRelationship|PersonNumber|LegalEmployerName|DateStart|WorkerType
MERGE|WorkRelationship|EMP10998|4Achievers India Ltd|2026-01-15|E

Q37. Write a SQL query in Oracle Fusion to find unpaid AP Invoices.

Live Coding Challenge

Query AP_INVOICES_ALL where payment_status_flag != 'Y'.

SELECT 
    invoice_num,
    invoice_date,
    invoice_amount,
    amount_paid,
    payment_status_flag
FROM ap_invoices_all
WHERE payment_status_flag IN ('N', 'P')
ORDER BY invoice_date DESC;

Q38. Write the Fast Formula syntax to validate an absence request duration.

Live Coding Challenge

We check duration against balance and return error flag if breached.

INPUTS ARE DURATION
IF DURATION > 15 THEN (
    VALID = 'N'
    ERROR_MESSAGE = 'Cannot request more than 15 consecutive days'
    RETURN VALID, ERROR_MESSAGE
)
VALID = 'Y'
RETURN VALID

Q39. Write the SQL query to inspect Subledger Accounting (SLA) entries.

Live Coding Challenge

Query XLA_AE_HEADERS and XLA_AE_LINES joining on ae_header_id.

SELECT 
    h.event_type_code,
    h.accounting_date,
    l.accounting_class_code,
    l.entered_dr,
    l.entered_cr
FROM xla_ae_headers h
JOIN xla_ae_lines l ON h.ae_header_id = l.ae_header_id
WHERE h.application_id = 200; -- 200 represents Payables

Q40. Write the FBDI macro CSV format header for loading GL Journals.

Live Coding Challenge

Standard CSV header fields for GL_INTERFACE table.

STATUS,LEDGER_ID,ACCOUNTING_DATE,USER_JE_SOURCE_NAME,USER_JE_CATEGORY_NAME,CURRENCY_CODE,ENTERED_DR,ENTERED_CR,SEGMENT1,SEGMENT2,SEGMENT3