# ALTER TABLE RENAME COLUMN

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RENAME COLUMN SQL keyword reference documentation.

Rename a column in an existing table.

:::caution

- New column names may only consist of letters, numbers and underscores `_`

:::

## Syntax

```questdb-sql
ALTER TABLE tableName RENAME COLUMN columnName TO newColumnName;
```

## Example

The following example renames an existing column called `sensor` to
`hum_sensor_1` from the table `measurements`:

```questdb-sql title="Renaming a column"
ALTER TABLE measurements RENAME COLUMN sensor TO hum_sensor_1;
```