text: CREATE TABLE UPOS(
     CHROMOSOME  INT  NOT NULL,
     POSITION    INT  NOT NULL
  );
  CREATE TABLE EXULANS(
     CHROMOSOME  INT  NOT NULL,
     POSITION    INT  NOT NULL,
     REFERENCE   TEXT NOT NULL,
     ALTERNATIVE TEXT,
     QUALITY     FLOAT,
     COVERAGE    INT NOT NULL,
     GENOTYPE    TEXT, -- genotype
     PL          TEXT, -- phred likelihoods afgerond ref
     GENOTYPE_BP TEXT, -- genotype in bases
  
     DIST_P      INT, -- distance related to SNP before
     DIST_N      INT, -- distance related to SNP after
     ORGANISM    INT,
     FOREIGN KEY(CHROMOSOME, POSITION) REFERENCES UPOS(CHROMOSOME, POSITION)
  );
  -- ALTER TABLE EXULANS
  -- ADD FOREIGN KEY (CHROMOSOME, POSITION) REFERENCES UPOS(CHROMOSOME, POSITION);
  