CREATE TABLE "vassal_states" (
  "state" text,
  "type" text,
  "name" text,
  "title" text,
  "royal_house" text
);

Question: Who held the title of Ruler?
SQL: SELECT "name" FROM "vassal_states" WHERE "title"='ruler';

Question: What type of state did the ruler have a title?
SQL: SELECT "type" FROM "vassal_states" WHERE "title"='ruler';

Question: In what state did Jing have the title of Marquis?
SQL: SELECT "state" FROM "vassal_states" WHERE "title"='marquis' AND "name"='jing';

Question: What was Gongbo's title?
SQL: SELECT "title" FROM "vassal_states" WHERE "name"='gongbo';

Question: What is the name of Yi's state?
SQL: SELECT "state" FROM "vassal_states" WHERE "name"='yi';