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Mysql rename column how to#

Towards that end, we have been asked to add a field for the credit card number in our members table. Let’s suppose that Myflix has introduced online billing and payments. “ADD COLUMN `column_name` `data_type`” is the command that tells MySQL server to add a new column named `column_name` with data type `data_type’.

“ALTER TABLE `table_name`” is the command that tells MySQL server to modify the table named `table_name`.

The basic syntax used to add a column to an already existing table is shown below ALTER TABLE `table_name` ADD COLUMN `column_name` `data_type` We can use the alter command to change the data type of a field from say string to numeric, change the field name to a new name or even add a new column in a table. The alter command comes in handy in such situations. They don’t want to lose the existing data but just want to incorporate the new information. Our database users are using it and then they realize some of the vital information was left out in the design phase. Let’s suppose that we have completed our database design and it has been implemented. The alter command is used to modify an existing database, table, view or other database objects that might need to change during the life cycle of a database. MySQL provides the ALTER function that helps us incorporate the changes to the already existing database design. As business requirements change, Database designs need changing as well. With time business requirements change as well. You have successfully changed the name of the column, changed the data type to y_data_type, and positioned the column after column_x.As the saying goes Change is the only constant For example: ALTER TABLE your_table_name CHANGE original_column_name new_col_name y_data_type AFTER column_x The CHANGE also allows you to place the column in a different position in the table by using the optional FIRST | AFTER column_name clause. Use additional options to further manipulate table columns.

The data_type element is mandatory, even if you want to keep the existing datatype. It can be used to rename a column and change the data type of that column with the same command.Įnter the following command in your MySQL client shell to change the name of the column and its definition: ALTER TABLE your_table_name CHANGE original_column_name new_col_name data_type The CHANGE clause offers important additions to the renaming process. If you need additional functions, such as changing the data definition, or position of a column, you need to use the CHANGE clause instead. The RENAME COLUMN clause can only be used to rename a column. ALTER TABLE RENAME is the existing syntax to rename the entire table. Note: The word COLUMN is obligatory for the ALTER TABLE RENAME COLUMN command. Keep in mind that you cannot rename a column to a name that already exists in the table. To change a column name, enter the following statement in your MySQL shell: ALTER TABLE your_table_name RENAME COLUMN original_column_name TO new_column_name Įxchange the your_table_name, original_column_name, and new_column_name with your table and column names. This clause is available since MySQL version 8.0. The simplest way to rename a column is to use the ALTER TABLE command with the RENAME COLUMN clause.

Mysql rename column how to#

How to Use the RENAME COLUMN Clause (MySQL 8.0) The commands are straightforward, and you may use the clause that fits your requirements best. The difference is that the CHANGE clause can also be used to alter the data types of a column. The RENAME COLUMN and CHANGE clause both allow for the names of existing columns to be altered. The function that concerns us the most is how to utilize ALTER TABLE to rename a column.Ĭlauses give us additional control over the renaming process. You can use it to add or delete columns, change the type of data within the columns, and even rename entire databases. Rename MySQL Column with ALTER TABLE CommandĪLTER TABLE is an essential command used to change the structure of a MySQL table.