CREATE TABLE "results_pool_b" (
  "date" text,
  "score" text,
  "set_1" text,
  "set_2" text,
  "set_3" text,
  "set_4" text,
  "set_5" text,
  "total" text
);

Question: What is Date, when Set 2 is 25-13?
SQL: SELECT "date" FROM "results_pool_b" WHERE "set_2"='25-13';

Question: What is Total, when Set 5 is NA, and when Set 2 is 25-13?
SQL: SELECT "total" FROM "results_pool_b" WHERE "set_5"='na' AND "set_2"='25-13';

Question: What is Score, when Date is Jun 16, and when Set 4 is 25-20?
SQL: SELECT "score" FROM "results_pool_b" WHERE "date"='jun 16' AND "set_4"='25-20';

Question: What is Set 2, when Score is 3-0, when Date is May 11, and when Set 1 is 25-20?
SQL: SELECT "set_2" FROM "results_pool_b" WHERE "score"='3-0' AND "date"='may 11' AND "set_1"='25-20';

Question: What is Set 4, when Set 1 is 25-18, and when Date is Jun 2?
SQL: SELECT "set_4" FROM "results_pool_b" WHERE "set_1"='25-18' AND "date"='jun 2';