How To Delete All Columns In Mysql

In this tutorial, we will learn how to delete all columns in a MySQL database table. This is a useful operation when you want to remove a table’s entire schema or effectively reset it while leaving the table structure intact. Note that performing this operation will result in the permanent loss of all data in the table’s columns.

Step 1: Connect to MySQL database

Before you can perform any operations on the MySQL database, you must establish a connection to it. You can do this using various tools and programming languages like MySQL Workbench, PHP, Python, or command-line. For the sake of simplicity, we will use the MySQL Command-Line client in this tutorial.

Open your MySQL Command-Line client and enter your credentials to connect to the desired database. Make sure you have the necessary privileges to execute commands on the database and its tables.

Step 2: Identify the table for column deletion

Choose the table in the database from which you want to delete all of the columns. You can display the list of tables in the database using the following command:

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SHOW TABLES;

Step 3: Display specific columns of the table

To see the columns that currently exist in the table, use the following command:

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DESCRIBE table_name;

Replace table_name with the actual name of the table.

Step 4: Delete columns

Now, you have to iterate through each column and delete them one by one using the following command:

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ALTER TABLE table_name DROP COLUMN column_name;

Replace table_name with the actual name of the table, and column_name with each specific column, you want to delete.

For example, if you have a table called “employees” with the columns “first_name”, “last_name”, and “age”, you would run the following commands:

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ALTER TABLE employees DROP COLUMN first_name;
ALTER TABLE employees DROP COLUMN last_name;
ALTER TABLE employees DROP COLUMN age;

Step 5: Verify the deletion

After deleting all the columns, you can verify their deletion using the DESCRIBE command as in Step 3:

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DESCRIBE table_name;

If no columns are displayed in the output, it means all the columns have been successfully deleted.

Full code

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SHOW TABLES;
 
DESCRIBE table_name;
ALTER TABLE table_name DROP COLUMN column_name;
DESCRIBE table_name;

Conclusion

In this tutorial, we learned how to delete all columns in a MySQL database table using the MySQL Command-Line client. If you prefer to use a different tool or programming language, the SQL commands used in this tutorial should still be applicable, but the method of execution may vary. Always remember that deleting columns will result in the permanent loss of all data within those columns.