public function findUniqueIndexes($table)
    {
        $query = <<<'SQL'
SELECT
    DIC.INDEX_NAME,
    DIC.COLUMN_NAME
FROM ALL_INDEXES DI
    INNER JOIN ALL_IND_COLUMNS DIC ON DI.TABLE_NAME = DIC.TABLE_NAME AND DI.INDEX_NAME = DIC.INDEX_NAME
WHERE
    DI.UNIQUENESS = 'UNIQUE'
    AND DIC.TABLE_OWNER = :schemaName
    AND DIC.TABLE_NAME = :tableName
ORDER BY DIC.TABLE_NAME, DIC.INDEX_NAME, DIC.COLUMN_POSITION
SQL;
        $result = [];
        $command = $this->db->createCommand($query, [
            ':tableName' => $table->name,
            ':schemaName' => $table->schemaName,
        ]);
        foreach ($command->queryAll() as $row) {
            $result[$row['INDEX_NAME']][] = $row['COLUMN_NAME'];
        }

        return $result;
    }
public function findUniqueIndexes($table)
    {
        $query = <<<'SQL'
SELECT
    DIC.INDEX_NAME,
    DIC.COLUMN_NAME
FROM ALL_INDEXES DI
    INNER JOIN ALL_IND_COLUMNS DIC ON DI.TABLE_NAME = DIC.TABLE_NAME AND DI.INDEX_NAME = DIC.INDEX_NAME
WHERE
    DI.UNIQUENESS = 'UNIQUE'
    AND DIC.TABLE_OWNER = :schemaName
    AND DIC.TABLE_NAME = :tableName
ORDER BY DIC.TABLE_NAME, DIC.INDEX_NAME, DIC.COLUMN_POSITION
SQL;
        $result = [];
        $command = $this->db->createCommand($query, [
            ':tableName' => $table->name,
            ':schemaName' => $table->schemaName,
        ]);
        foreach ($command->queryAll() as $row) {
            $result[$row['INDEX_NAME']][] = $row['COLUMN_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