How to Select All Columns Except One in MySQL?

Retrieving All but One Column from a MySQL Table

Question:

In a MySQL database, how can you retrieve all columns except for a specific one in a particular table?

Answer:

Although this may seem like a straightforward task, MySQL does not provide a built-in method for excluding specific columns in a SELECT statement. However, using a combination of dynamic SQL and stored procedures, it is possible to achieve this functionality.

Solution:

Follow these steps to retrieve all columns except one in a MySQL table:

1. Create a Stored Procedure:

DELIMITER //

CREATE PROCEDURE get_all_columns_except(
    IN table_name VARCHAR(255),
    IN database_name VARCHAR(255),
    IN excluded_column VARCHAR(255)
)
BEGIN

    -- Dynamically build the SELECT statement
    SET @sql = CONCAT('SELECT ', (SELECT REPLACE(GROUP_CONCAT(COLUMN_NAME), excluded_column, '') FROM INFORMATION_SCHEMA.COLUMNS WHERE TABLE_NAME = table_name AND TABLE_SCHEMA = database_name), ' FROM ', table_name);

    -- Prepare the statement for execution
    PREPARE stmt1 FROM @sql;

    -- Execute the statement
    EXECUTE stmt1;

END //

DELIMITER ;

2. Call the Stored Procedure:

Once the stored procedure is created, you can call it with the following command:

CALL get_all_columns_except('table_name', 'database_name', 'excluded_column_name');

3. Parameter Substitution:

Replace "table_name", "database_name", and "excluded_column_name" with the actual values.

Example:

To retrieve all columns except for the "last_name" column in the "employees" table in the "company_db" database, you would call the stored procedure as follows:

CALL get_all_columns_except('employees', 'company_db', 'last_name');

This approach allows you to select all columns in a table, automatically omitting a specified column, even if the table has a large number of columns.

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