Difference between DELETE, DROP and TRUNCATE table in SQL

The DELETE statement is used to remove specific records from a table based on a given condition. The DROP TABLE statement is used to delete an entire table, including its structure and data. Where as the TRUNCATE TABLE statement removes all records from a table but retains the table structure.

Please read detailed articles, DELETE table in SQL

DROP table in SQL

TRUNCATE table in SQL

Examples of these commands

Database Structure:

StudentID	FirstName	LastName	Age	Course
1	John	Doe	21	Computer Science
2	Jane	Smith	20	Data Science
3	Bob	Johnson	22	Web Development
4	Alice	White	23	Cybersecurity

DROP TABLE Statement:

-- Example: Dropping the Students table
DROP TABLE Students;

Output: The Students table is completely removed.

TRUNCATE TABLE Statement:

-- Example: Truncating the Students table
TRUNCATE TABLE Students;

Output:

StudentID	FirstName	LastName	Age	Course
0			0

DELETE Statement:

-- Example: Deleting a student record
DELETE FROM Students WHERE StudentID = 2;

Output:

StudentID	FirstName	LastName	Age	Course
1	John	Doe	21	Computer Science
3	Bob	Johnson	22	Web Development
4	Alice	White	23	Cybersecurity

Difference between DROP and DELETE

Aspect	DROP TABLE	DELETE
Purpose	Remove an entire table, including structure and data.	Remove specific records from a table.
Granularity	Operates at the table level.	Operates at the row level.
Irreversibility	Irreversible. Once executed, the table is gone.	Reversible. Removes specific rows but retains the table structure.
Performance	May take longer, especially for large tables.	Can be slower for large datasets, especially when removing a significant portion of records.
Syntax	DROP TABLE table_name;	DELETE FROM table_name WHERE condition;

Difference between Delete and TRUNCATE

Aspect	DELETE	TRUNCATE TABLE
Purpose	Remove specific records from a table based on a condition.	Remove all records from a table, but retain the table structure.
Granularity	Operates at the row level, allowing targeted removal.	Operates at the table level, removing all records.
Transaction Log	Generates individual row deletion entries in the transaction log.	Doesn’t log individual row deletions, resulting in less transaction log activity.
Reset Identity Columns	Doesn’t automatically reset identity columns to their seed value.	Automatically resets identity columns to their seed value, effectively resetting auto-incrementing primary key values.
Performance	Can be slower, especially for large datasets, due to logging.	Generally faster, especially for bulk data removal, as it doesn’t log individual row deletions.
Syntax	DELETE FROM table_name WHERE condition;	TRUNCATE TABLE table_name;

Difference between DROP and TRUNCATE

Aspect	DROP TABLE	TRUNCATE TABLE
Purpose	Completely removes an entire table and its structure.	Removes all records from a table but retains the table structure for future use.
Granularity	Operates at the table level, deleting the entire entity.	Operates at the table level, removing all records.
Irreversibility	Irreversible action. Once executed, the table is permanently deleted.	Reversible. The table structure remains, and the operation can be rolled back.
Transaction Log	No impact on the transaction log since the entire table is deleted at once.	Less transaction log activity compared to DELETE.
Reset Identity Columns	Doesn’t apply, as the entire table, including identity columns, is removed.	Automatically resets identity columns to their seed value.
Performance	May take longer, especially for large tables.	Generally faster, especially for bulk data removal, as it doesn’t log individual row deletions.
Syntax	DROP TABLE table_name;	TRUNCATE TABLE table_name;