'🛠️ Basics of `ALTER TABLE` in SQL: Modifying Table Structures in Detail 📋🔄'

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The `ALTER TABLE` statement in SQL is used to modify an existing table’s structure. It allows you to:

- **Add Columns**: Introduce new columns to a table.
- **Drop Columns**: Remove existing columns from a table.
- **Modify Columns**: Change the data type or size of existing columns.
- **Rename Columns**: Change the name of a column.
- **Add Constraints**: Define or modify constraints like primary keys, foreign keys, or unique constraints.
- **Drop Constraints**: Remove existing constraints from the table.

The `ALTER TABLE` statement provides flexibility to adapt table structures to evolving data requirements.