CREATE TABLE "project_636_significant_dates" (
  "operator" text,
  "shipyard" text,
  "project" text,
  "commissioned" text,
  "status" text
);

Question: What is the commissioned for Vietnam?
SQL: SELECT "commissioned" FROM "project_636_significant_dates" WHERE "operator"='vietnam';

Question: What is the commissioned with a 636.3 project, and ordered status?
SQL: SELECT "commissioned" FROM "project_636_significant_dates" WHERE "project"='636.3' AND "status"='ordered';