Confused about DROP and DELETE in SQL? This article has your answers! Unravel the difference between DROP and DELETE statements with a real-life example. Let’s dive into the world of SQL together!
DELETE and DROP statements in SQL are used to remove the records from the databases. But if both serve the same purpose, why do we need both commands? This article will discuss the difference between these commands, i.e., the difference between Drop and Delete in SQL.
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Let’s start the article with the tabular difference between Delete and Drop statements in SQL.
Table of Content
- Difference Between Drop and Delete: Drop vs Delete
- What is DROP in SQL?
- What is DELETE in SQL?
- Example of DROP and DELETE statement in SQL
- Key Difference Between DELETE and DROP
What is the Difference Between DROP and DELETE?
|SQL Statement Type||Data Definitinition Language (DDL)||Data Manipulation Language (DML)|
|Syntax||DROP TABLE table_name||DELETE FROM table_name WHERE condition|
|Purpose||It removes entire database objects (tables, indexes, views, etc.)||Removes specific rows of data from a table.|
|Conditional Deletion||Not applicable; removes entire objects.||Removes specified rows based on the specified conditions.|
|Precautions||Backup data before executing since the data is lost permanently. No data recovery option is available.||Include a WHERE clause to target specific rows. Deleted data can be recovered using transactions.|
|Performance||Potentially resource-intensive.||It may be slower with large datasets as it removes data one by one.|
|Dependencies||It may impact other objects that are dependent on the dropped objects.||Does not affect the other objects.|
What is DROP in SQL?
DROP command in SQL removes table definition and all the data from one or more database tables.
- It is a Data Definition Language (DDL) command.
- It removes all data/indexes/triggers/constraints/ and permission specific to that table
- SQL DROP TABLE statement permanently removes the data from the tables and the metadata that defines the table in the data dictionary.
- Dropping a table or a database is an irreversible process, so be extra careful while dropping the table or database.
- SQL DROP TABLE command can’t be used to remove a table that a Foreign Key references.
The syntax to drop the table is a straightforward DROP TABLE command followed by the table names, i.e.
DROP TABLE table_names;
Must Read: How to use DROP statement in SQL?
What is DELETE in SQL?
Like SQL’s DROP statement, the DELETE command is also used to remove data. Still, unlike the DROP statement, DELETE does not delete the entire database object but selectively removes the row based on the specified conditions while preserving the data structure.
- It is Data Manipulation Language (DML) command.
- It only affects the data within the table and doesn’t alter the table’s structure or metadata.
- The DELETE statement is less dangerous than the DROP statement, as the removed data can be rollback using transactions.
- If you want to remove particular record from the table (i.e., based on particular condition)
DELETE FROM table_name WHERE condition
- If you want to remove all the record from the table
DELETE FROM table_name;
The above command will remove all the record from the table, but the table structure, attributes, and indexes will be intact.
Must Read: How to use DELETE statement in SQL?
Now, let’s take an example and perform both the operations simultaneously and check what will be the output.
Example of DELETE and DROP Statement in SQL
Let’s consider a dataset.
|1004||Ramesh||Associate Senior Executive||IT|
Problem Statement: The above table contains the record of the employees (employee id, name, designation, and department). Ramesh from the IT team left the company, so the company has decided to remove the record of Ramesh from the ‘Employee’ table.
Using DROP Statement
DROP TABLE Employee;
The above command will remove the entire ‘Employee’ table along with its data, i.e., all the data will be lost, including those who are currently working in the company. This is not the desired result, as we only want to remove the record of the employee named Ramesh.
Using DELETE Statement
DELETE FROM Employee WHERE Emp_ID = 1004;
From the above output, you can easily visualize the Ramesh (Emp_ID = 1004) record being removed from the table while all other records are unchanged.
Key Differences and Similarities in DELETE and DROP Statements
- Both DROP and DELETE statements are used to remove data in SQL.
- DROP is a Data Definition Language (DDL), whereas DELETE is a Data Manipulation Language (DML).
- The SQL DELETE statement removes specific data rows from a table based on the given condition. In contrast, the DROP statement permanently removes the entire database objects, such as tables, indexes, or views, from the database schema.
- Changes made using the DROP statement are permanent and can’t be undone, whereas the changes made using the DELETE statement can be rollbacked using transaction.
- DROP statement does not allow conditional deletion of the table, i.e., it deletes the entire object from the schema. In contrast, the DELETE condition allows selected data removal using the WHERE clause.
DROP and DELETE statements in the SQL are used to remove the data, but they operate at different levels. DROP command in SQL deletes entire database objects and their data, whereas the DELETE command removes specific rows from the table (specified by the WHERE clause). In this article, we have briefly discussed the difference between DROP and DELETE statements in SQL with the help of examples.
Hope you will like the article.
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What is DELETE statement in SQL?
Like SQL's DROP statement, the DELETE command is also used to remove data. Still, unlike the DROP statement, DELETE does not delete the entire database object but selectively removes the row based on the specified conditions while preserving the data structure.
What is DROP statement in SQL?
DROP command in SQL removes table definition and all the data from one or more database tables. It is a Data Definition Language.
What is the difference between DELETE and DROP statement in SQL?
DROP command in SQL is a Data Definition Language, whereas the DELETE command in SQL is a Data Manipulation Language. DROP command does not allow conditional deletion, i.e., once the table is dropped it cannot be recovered, but when data is removed using DELETE, it can be rollback using transactions.
Why to use DROP and DELETE statement in SQL?
DROP and DELETE statement in SQL are used to remove the data. DROP statement remove the entire database object, whereas the DELETE statement removes the specified record from the table.
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