import Database from 'better-sqlite3';
export declare function mergeNodeText(title: string | null, content: string | null): string;
export interface MigrateMaps {
    labelToUid: Map<string, string>;
    nodeIdToUid: Map<string, string>;
}
export declare function migrateTree(v1: Database.Database, v2: Database.Database): MigrateMaps;
export interface LinkMigration {
    resolved: number;
    oRefTargets: string[];
    dangling: {
        src: string;
        dst: string;
    }[];
}
export declare function migrateLinks(v1: Database.Database, v2: Database.Database, maps: MigrateMaps): LinkMigration;