How many times is the accession number xp_001843282?
CREATE TABLE "orthologs" (
  "species" text,
  "common_name" text,
  "protein_name" text,
  "accession_number" text,
  "nt_length" text,
  "nt_identity" text,
  "aa_length" text,
  "aa_identity" text,
  "e_value" text
);
SELECT COUNT("common_name") FROM "orthologs" WHERE "accession_number"='XP_001843282';