用于LINQ查询的可比较SQL？

Question

是否有一个SQL查询可以提供与以下LINQ语句相同的结果？

DataTable dtAll1 = userData1.AsEnumerable()
    .Where(ra => !userData2.AsEnumerable()
    .Any(rb => rb.Field<string>("A") == ra.Field<string>("B")))
    .CopyToDataTable();

Answer 1

SELECT
    *
  FROM
    userData1 AS ra
  WHERE
    NOT EXISTS (SELECT * FROM userData2 AS rb WHERE ra.B = rb.A)

（从EXISTS更新为NOT EXISTS。）