Inserting, updating, and deleting records in MYSQL

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In MySQL, you can perform basic database operations like inserting, updating, and deleting records using SQL statements. Here's how you can do each of these operations:

Inserting Records:

To insert a new record into a table, you can use the INSERT INTO statement. Here's the basic syntax:

Inserting, updating, and deleting records in MYSQL


sql code

INSERT INTO table_name (column1, column2, ...)

VALUES (value1, value2, ...);

Example:

sql code

INSERT INTO employees (first_name, last_name, email)

VALUES ('John', 'Doe', 'johndoe@example.com');

This will insert a new record into the "employees" table with the specified values.

Updating Records:

To update existing records in a table, you can use the UPDATE statement. Here's the basic syntax:

sql code

UPDATE table_name

SET column1 = value1, column2 = value2, ...

WHERE condition;

Example:

sql code

UPDATE employees

SET salary = 60000

WHERE last_name = 'Doe';

This will update the "salary" column of all employees with the last name 'Doe' to 60000.

Deleting Records:

To delete records from a table, you can use the DELETE FROM statement. Here's the basic syntax:

sql code

DELETE FROM table_name

WHERE condition;

Example:

sql code

DELETE FROM employees

WHERE last_name = 'Doe';

This will delete all records from the "employees" table where the last name is 'Doe'.

Remember to be cautious when performing DELETE operations, especially without a WHERE clause, as it can delete all records from a table.

Always make sure to have backups and test your SQL statements carefully before running them in a production environment to avoid data loss.

Additionally, consider using transactions and adding error handling to ensure the integrity of your data when performing these operations in a real-world application.

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