> ## Documentation Index
> Fetch the complete documentation index at: https://docs.regatta.dev/llms.txt
> Use this file to discover all available pages before exploring further.

# UPDATE

Modifies rows in an existing table.

## Synopsis

```
UPDATE table_name[ [ AS ] alias ]
  SET { column_name = { expression | DEFAULT } |
        ( column_name [, ...] ) = ( { expression | DEFAULT } [, ...] ) |
        ( column_name [, ...] ) = ( sub-SELECT )
      } [, ...]
  [ WHERE condition ]
  [ RETURNING output_expression [[ AS ] output_name ] [, ...] ]
```

## Description

The `UPDATE` command modifies the values of specific columns in all rows that satisfy the command condition.

## Parameters

**`table_name`**

The name of the table to modify its rows.

**`alias`**

A substitute alias name for `table_name`. The alias name should match the [Identifiers Limitations](/sql/appendices/indentifiers-limitations).

**`SET`**

The requested change. Contains a tuple of column names and a tuple of their new values.

**`column_name`**

The name(s) of the column(s) to modify. The columns should not include the table name (`SET tab1.c_id = 1` is invalid).

**`expression`**

The new value to replace the existing value per column.

**`DEFAULT`**

Set the new column value to the column default value as set for the column in the table definition.

**`sub-SELECT`**

Subquery that returns exactly one row. The subquery returned columns should match the `SET` clause columns and their data types.

<Note>
  Note: If the subquery returns no rows, the value of all the updated columns in the updated rows is set to NULL.
</Note>

**`WHERE`**

A filter to decide which rows in the table to update. If no condition is set, all the rows in the table are updated.

The `WHERE` clause can contain the rows `ROWID` with ‘=’ or `‘IN` (`<`list of literals`>`)’
condition.

**`RETURNING output_expression`**

Returns the given expression for every row modified by the command. Refer to the `expression`
parameter of [SELECT](/sql/dql/select/select#parameters) for specification of the **output\_expression** parameter.

## Outputs

On successful completion, the `UPDATE` command returns the count of the updated rows.

## Examples

Update the rows based on a simple predicate:

```sql theme={null}
UPDATE orders SET o_date = '2022-01-01' WHERE c_custkey = 1
```

Update multiple columns and return the update rows ROWIDs:

```sql theme={null}
UPDATE orders SET o_date = '2022-01-01', o_totalprice = O_totalprice * 0.1
WHERE o_name = 'order of John Doe1' AND o_date > '2000-01-01'
RETURNING ROWID;
```

### Update a table based on ROWID

```sql theme={null}
UPDATE orders SET o_date = '2022-01-01'
WHERE ROWID in (12345678, 12345677, 12345676);
```

### Update a table using a result from a non-correlated subquery

```sql theme={null}
UPDATE orders
SET o_totalprice = (SELECT MAX(o_totalprice * 1.10) FROM old_orders)
WHERE o_date > '2022-12-12';
```

## Compatibility

The `UPDATE` command conforms to the SQL standard with the exception of the RETURNING functionality.