Answers for "sqlite update or insert if not exists"

sqlite insert if not exists

#id column is assumed to be primary key

INSERT INTO destination_table(id,name) 
SELECT id, name
FROM source_table s
WHERE NOT EXISTS (
  SELECT 1
  FROM destination_table d
  WHERE d.id = s.id
);

sqlite update where exists

UPDATE employees
SET hire_date = (SELECT departments.start_date
                 FROM departments
                 WHERE departments.department_id = employees.department_id
                 AND departments.department_name = 'HR')
WHERE EXISTS (SELECT *
              FROM departments
              WHERE departments.department_id = employees.department_id
              AND departments.department_name ='HR');