# ALTER TABLE ADD COLUMNS
<a name="alter-table-add-columns"></a>

Adds one or more columns to an existing table. When the optional `PARTITION` syntax is used, updates partition metadata. 

## Synopsis
<a name="synopsis"></a>

```
ALTER TABLE table_name 
  [PARTITION 
   (partition_col1_name = partition_col1_value
   [,partition_col2_name = partition_col2_value][,...])]
  ADD COLUMNS (col_name data_type)
```

## Parameters
<a name="parameters"></a>

**PARTITION (partition\$1col\$1name = partition\$1col\$1value [,...])**  
Creates a partition with the column name/value combinations that you specify. Enclose `partition_col_value` in quotation marks only if the data type of the column is a string.

**ADD COLUMNS (col\$1name data\$1type [,col\$1name data\$1type,...])**  
Adds columns after existing columns but before partition columns.

## Examples
<a name="examples"></a>

```
ALTER TABLE events ADD COLUMNS (eventowner string)
```

```
ALTER TABLE events PARTITION (awsregion='us-west-2') ADD COLUMNS (event string)
```

```
ALTER TABLE events PARTITION (awsregion='us-west-2') ADD COLUMNS (eventdescription string)
```

## Notes
<a name="alter-table-add-columns-notes"></a>
+ To see a new table column in the Athena Query Editor navigation pane after you run `ALTER TABLE ADD COLUMNS`, manually refresh the table list in the editor, and then expand the table again.
+ `ALTER TABLE ADD COLUMNS` does not work for columns with the `date` datatype. To workaround this issue, use the `timestamp` datatype instead.