public function findUniqueIndexes($table)
    {
        $result = [];
        foreach ($this->findTableConstraints($table, 'UNIQUE') as $row) {
            $result[$row['index_name']][] = $row['field_name'];
        }

        return $result;
    }
public function findUniqueIndexes($table)
    {
        $result = [];
        foreach ($this->findTableConstraints($table, 'UNIQUE') as $row) {
            $result[$row['index_name']][] = $row['field_name'];
        }

        return $result;
    }
Returns all unique indexes for the given table.

Each array element is of the following structure:

```php
[
'IndexName1' => ['col1' [, ...]],
'IndexName2' => ['col2' [, ...]],
]
```

@param TableSchema $table the table metadata
@return array all unique indexes for the given table.
@since 2.0.4