CREATE TABLE "echo_ii_class_significant_dates" (
  "num" text,
  "shipyard" text,
  "laid_down" text,
  "launched" text,
  "commissioned" text,
  "fleet" text,
  "status" text
);

Question: When were the ships launched that were laid down on september 1, 1964?
SQL: SELECT "launched" FROM "echo_ii_class_significant_dates" WHERE "laid_down"='September 1, 1964';

Question: List the # for ships commissioned on december 18, 1965.
SQL: SELECT "num" FROM "echo_ii_class_significant_dates" WHERE "commissioned"='December 18, 1965';

Question: List the # for ships commissioned on september 30, 1967.
SQL: SELECT "num" FROM "echo_ii_class_significant_dates" WHERE "commissioned"='September 30, 1967';

Question: When were ships laid down that were commissioned on october 29, 1965?
SQL: SELECT "laid_down" FROM "echo_ii_class_significant_dates" WHERE "commissioned"='October 29, 1965';