UniqueConstraintNode
interface UniqueConstraintNode  extends OperationNode {
readonly columns: ReadonlyArray<ColumnNode>;
readonly kind: "UniqueConstraintNode";
readonly name?: IdentifierNode;
readonly nullsNotDistinct?: boolean;
}const UniqueConstraintNode: Readonly<{
is(node: OperationNode): node is UniqueConstraintNode; 
create(
columns: string[],
constraintName?: string,
nullsNotDistinct?: boolean,
): UniqueConstraintNode; cloneWith(node: UniqueConstraintNode, props: UniqueConstraintNodeProps): UniqueConstraintNode; 
}>;