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The ALTER TABLE statement is used to add, delete, or modify columns in an existing table. The ALTER TABLE statement is also used to add and drop various constraints on an existing table. ALTER TABLE - ADD Column. To add a column in a table, use the following syntax: ALTER TABLE table_name. ADD column_name datatype;
To add a new column to an existing table, use the following syntax: ALTER TABLE table_name ADD column_name data_type [column_constraint]; For example, to add a new column named email of data type VARCHAR(50) to the students table, you would use the following statement: ALTER TABLE students ADD email VARCHAR(50); Modify an Existing Column
If you want to add multiple columns to a table at once using a single ALTER TABLE statement, you use the following syntax: ALTER TABLE table_name. ADD. column_name_1 data_type_1 column_constraint_1, column_name_2 data_type_2 column_constraint_2, ..., column_name_n data_type_n column_constraint_n;
ALTER TABLE ADD column: Syntax 1: To add a column in the existing table. ALTER TABLE table_name ADD column_name column_definition [ FIRST | AFTER column_name ];
ALTER TABLE − ADD Column. Adding a new column is like giving your students a new characteristic to track. Let's add an 'email' column: ALTER TABLE students. ADD email VARCHAR (100); After running this command, our students table will now have an additional column for email addresses. It's that simple! ALTER TABLE − DROP COLUMN.
Use MySQL ADD COLUMN clause in the ALTER TABLE statement to add one or more columns to a table.
You can add a column after an existing column (ATER column_name) or as the first column (FIRST). If you omit this clause, the column is appended at the end of the column list of the table. The following example uses the ALTER TABLE ADD statement to add a column at the end of the vehicles table: ALTER TABLE vehicles.
