sharing_package_index is a sub-index of sharing_insert_index and
therefore unnecessary.
CREATE TABLE sharing (package1 TEXT, package2 TEXT, func1 TEXT, func2 TEXT, files INTEGER, size INTEGER, FOREIGN KEY (package1) REFERENCES package(package) ON DELETE CASCADE, FOREIGN KEY (package2) REFERENCES package(package) ON DELETE CASCADE);
CREATE INDEX sharing_insert_index ON sharing (package1, package2, func1, func2);
-CREATE INDEX sharing_package_index ON sharing (package1);
CREATE TABLE duplicate (cid INTEGER PRIMARY KEY, FOREIGN KEY (cid) REFERENCES content(id) ON DELETE CASCADE);