What network has an aspect of 4:3 and a PSIP Short Name of qvc?
CREATE TABLE "digital_channels" (
  "channel" real,
  "video" text,
  "aspect" text,
  "psip_short_name" text,
  "network" text
);
SELECT "network" FROM "digital_channels" WHERE "aspect"='4:3' AND "psip_short_name"='qvc';