DBMS-Lab_File/Experiment 08.sql at main · Saksha2721/DBMS-Lab_File · GitHub

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CREATE TABLE BankAccounts (
    AccountID INT PRIMARY KEY,
    AccountHolder VARCHAR(50),
    Balance DECIMAL(10,2) NOT NULL
) ENGINE=InnoDB;

INSERT INTO BankAccounts VALUES
(101, 'Aarav Sharma', 10000.00),
(102, 'Ananya Verma', 8000.00),
(103, 'Rohan Gupta', 5000.00);

SELECT * FROM BankAccounts;

START TRANSACTION;

UPDATE BankAccounts
SET Balance = Balance - 1000
WHERE AccountID = 101;

UPDATE BankAccounts
SET Balance = Balance + 1000
WHERE AccountID = 102;

COMMIT;

SELECT * FROM BankAccounts;

START TRANSACTION;

UPDATE BankAccounts
SET Balance = Balance - 500
WHERE AccountID = 101;

SELECT * FROM BankAccounts
WHERE AccountID = 101;

ROLLBACK;

SELECT * FROM BankAccounts
WHERE AccountID = 101;

START TRANSACTION;

UPDATE BankAccounts
SET Balance = Balance - 200
WHERE AccountID = 101;

SAVEPOINT sp1;

UPDATE BankAccounts
SET Balance = Balance + 200
WHERE AccountID = 102;

ROLLBACK TO SAVEPOINT sp1;

COMMIT;

SELECT * FROM BankAccounts;

START TRANSACTION;

UPDATE BankAccounts
SET Balance = Balance - 1000
WHERE AccountID = 101;

ROLLBACK;

SELECT * FROM BankAccounts;

SET SESSION TRANSACTION ISOLATION LEVEL READ COMMITTED;

START TRANSACTION;

SELECT Balance
FROM BankAccounts
WHERE AccountID = 101;

COMMIT;

SET SESSION TRANSACTION ISOLATION LEVEL REPEATABLE READ;

START TRANSACTION;

SELECT Balance
FROM BankAccounts
WHERE AccountID = 101;

COMMIT;

SET SESSION TRANSACTION ISOLATION LEVEL READ COMMITTED;

START TRANSACTION;

SELECT Balance
FROM BankAccounts
WHERE AccountID = 101;

COMMIT;

START TRANSACTION;

UPDATE BankAccounts
SET Balance = Balance + 500
WHERE AccountID = 101;

COMMIT;

START TRANSACTION;

SELECT Balance
FROM BankAccounts
WHERE AccountID = 101;

COMMIT;