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ALTER
With ALTER we are able to perform operation on table structure such as :
adding, deleting, renaming, change data type for column, adding or deleting
index for column.
Syntax
ALTER TABLE `column_name` specification_of_alter_operation
Syntax for adding new table column
ALTER TABLE `table_name`
ADD `column_name` data_type
Syntax for deleting column from table
ALTER TABLE `table_name`
DROP COLUMN `column_name`
Syntax for changing data type for column
ALTER TABLE `table_name`
MODIFY `column_name` data_type
Syntax for renaming column
ALTER TABLE `table_name`
CHANGE `old_column_name` `new_column_name` data_type
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