![]() The following statement allows you to modify multiple columns: ALTER TABLE table_nameįirst, show the current columns of the vehicles table: Then, modify the note column: ALTER TABLE vehiclesįinally, show the column list of the vehicles table to verify the change: DESCRIBE vehicles Ĭode language: SQL (Structured Query Language) ( sql ) 2) Modify multiple columns ![]() Suppose that you want to change the note column a NOT NULL column with a maximum of 100 characters.įirst, show the column list of the vehicles table: DESCRIBE vehicles It’s a good practice to view the attributes of a column before modifying it. Here is the basic syntax for modifying a column in a table: ALTER TABLE table_name This statement shows the new structure of the vehicles table: DESCRIBE vehicles Ĭode language: SQL (Structured Query Language) ( sql ) MySQL ALTER TABLE – Modify columns 1) Modify a column To add multiple columns to a table, you use the following form of the ALTER TALE ADD statement: ALTER TABLE table_nameįor example, this statement adds two columns color and note to the vehicles table: ALTER TABLE vehicles This statement shows the column list of the vehicles table: DESCRIBE vehicles Īs shown clearly from the output, the column model has been added to the vehicles table. The following example uses the ALTER TABLE ADD statement to add a column at the end of the vehicles table: ALTER TABLE vehicles If you omit this clause, the column is appended at the end of the column list of the table. You can add a column after an existing column ( ATER column_name) or as the first column ( FIRST). FIRST | AFTER column_name specify the position of the new column in the table.column_definition– specify the datatype, maximum size, and column constraint of the new column. ![]()
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