ACID properties in DBMS Theory - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to identify the ACID property that ensures all parts of a transaction are completed or none at all.

DBMS Theory

The ACID property that guarantees a transaction is fully completed or fully rolled back is called [1].

Drag options to blanks, or click blank then click option'

ADurability

BIsolation

CAtomicity

DConsistency

Attempts:

3 left

💡 Hint

Common Mistakes

Confusing Atomicity with Durability or Consistency.

Atomicity means a transaction is treated as a single unit. It either completes fully or does not happen at all, ensuring no partial updates.

2fill in blank

medium

Complete the code to identify the ACID property that ensures database remains accurate after a transaction.

DBMS Theory

The ACID property that ensures the database moves from one valid state to another is called [1].

Drag options to blanks, or click blank then click option'

AConsistency

BAtomicity

CIsolation

DDurability

Attempts:

3 left

💡 Hint

Common Mistakes

Mixing up Consistency with Atomicity or Isolation.

Consistency ensures that any transaction will bring the database from one valid state to another, preserving database rules.

3fill in blank

hard

Fix the error in the statement about the ACID property that controls concurrent transactions.

DBMS Theory

The ACID property that ensures transactions do not interfere with each other is called [1].

Drag options to blanks, or click blank then click option'

AIsolation

BAtomicity

CDurability

DConsistency

Attempts:

3 left

💡 Hint

Common Mistakes

Confusing Isolation with Atomicity or Durability.

Isolation means that concurrent transactions are executed as if they were sequential, preventing interference.

4fill in blank

hard

Fill both blanks to complete the description of the ACID property that guarantees permanent changes after commit.

DBMS Theory

The ACID property called [1] ensures that once a transaction is committed, its changes are [2] even if the system crashes.

Drag options to blanks, or click blank then click option'

ADurability

BAtomicity

CPermanent

DTemporary

Attempts:

3 left

💡 Hint

Common Mistakes

Choosing Atomicity or Temporary for permanence.

Durability guarantees that once a transaction commits, its changes are permanent and survive system failures.

5fill in blank

hard

Fill all three blanks to complete the dictionary comprehension describing ACID properties and their meanings.

DBMS Theory

acid_properties = {"Atomicity": "[1]", "Consistency": "[2]", "Durability": "[3]"}

Drag options to blanks, or click blank then click option'

Aall or nothing execution

Bdatabase rules preserved

Cchanges saved permanently

Dtransactions isolated

Attempts:

3 left

💡 Hint

Common Mistakes

Mixing Isolation with these three properties.

This dictionary maps ACID properties to simple explanations: Atomicity means all or nothing execution, Consistency means database rules preserved, and Durability means changes saved permanently.

Practice

1. Which of the following ACID properties ensures that a transaction is completed fully or not at all?

easy

A. Atomicity

B. Consistency

C. Isolation

D. Durability

Solution

1. Step 1: Understand Atomicity in transactions

   Atomicity means a transaction must be all or nothing; it cannot be partially done.

2. Step 2: Compare with other ACID properties

   Consistency ensures data correctness, Isolation manages concurrent transactions, Durability guarantees data permanence after commit.

3. Final Answer:

   Atomicity -> Option A

4. Quick Check:

   All or nothing = Atomicity [OK]

Hint: All or nothing means Atomicity [OK]

Common Mistakes:

• Confusing Atomicity with Consistency
• Mixing Isolation with Durability
• Thinking Durability means transaction completeness

2. Which ACID property ensures that once a transaction is committed, its changes are permanent even if the system crashes?

easy

A. Consistency

B. Isolation

C. Atomicity

D. Durability

Solution

1. Step 1: Define Durability in ACID

   Durability guarantees that committed data is saved permanently and survives system failures.

2. Step 2: Differentiate from other properties

   Isolation controls transaction interference, Atomicity ensures full completion, Consistency maintains valid data states.

3. Final Answer:

   Durability -> Option D

4. Quick Check:

   Permanent changes after commit = Durability [OK]

Hint: Permanent data after commit means Durability [OK]

Common Mistakes:

• Confusing Durability with Isolation
• Thinking Atomicity means permanence
• Mixing Consistency with Durability

3. Consider a database transaction that updates two tables. If the transaction is interrupted after updating the first table but before the second, which ACID property prevents partial updates?

medium

A. Atomicity

B. Isolation

C. Durability

D. Consistency

Solution

1. Step 1: Analyze partial update scenario

   Partial updates mean some changes are saved while others are not, which is not allowed.

2. Step 2: Identify ACID property preventing partial updates

   Atomicity ensures the transaction is fully completed or fully rolled back, preventing partial changes.

3. Final Answer:

   Atomicity -> Option A

4. Quick Check:

   All or nothing update = Atomicity [OK]

Hint: Partial updates prevented by Atomicity [OK]

Common Mistakes:

• Choosing Durability for partial update
• Confusing Isolation with Atomicity
• Assuming Consistency handles partial updates

4. A developer notices that two transactions running at the same time cause incorrect data results. Which ACID property should be checked to fix this concurrency issue?

medium

A. Atomicity

B. Durability

C. Isolation

D. Consistency

Solution

1. Step 1: Understand concurrency problem

   Concurrent transactions interfering cause data errors due to lack of proper separation.

2. Step 2: Identify ACID property managing concurrency

   Isolation ensures transactions do not affect each other's intermediate states, preventing conflicts.

3. Final Answer:

   Isolation -> Option C

4. Quick Check:

   Concurrency control = Isolation [OK]

Hint: Concurrency issues fixed by Isolation [OK]

Common Mistakes:

• Mixing Isolation with Atomicity
• Thinking Durability controls concurrency
• Confusing Consistency with Isolation

5. A banking system must ensure that money transfer transactions are safe and reliable. Which combination of ACID properties best guarantees that money is neither lost nor duplicated during transfers?

hard

A. Consistency and Isolation

B. Atomicity and Isolation

C. Atomicity and Durability

D. Durability and Consistency

Solution

1. Step 1: Identify requirements for safe money transfer

   Money must not be lost (all steps complete) and no interference between transactions.

2. Step 2: Match requirements to ACID properties

   Atomicity ensures full completion or rollback, Isolation prevents concurrent transaction conflicts.

3. Step 3: Evaluate other options

   Durability ensures permanence but does not prevent duplication; Consistency ensures valid data but not transaction completeness or isolation.

4. Final Answer:

   Atomicity and Isolation -> Option B

5. Quick Check:

   Complete and separate transactions = Atomicity + Isolation [OK]

Hint: Safe transfers need Atomicity + Isolation [OK]

Common Mistakes:

• Choosing Durability alone
• Ignoring Isolation for concurrency
• Confusing Consistency with transaction completeness