SELECT A.* 
  FROM (SELECT ROW_NUMBER() OVER(ORDER BY tls.ServerId asc) AS RowNum,
               tls.ServerId AS ServerId, 
               tls.SystemId AS SystemId, 
               tlak.id      AS ApiId, 
               tlak.ApiKey  AS ApiKey, 
               COALESCE(CONVERT(CHAR(10), tlak.ExpiredAt, 120), '-') AS ExpiredAt, 
               tlak.policyLookupYn   AS PolicyLookupYn,
               tlak.fileInfoLookupYn AS FileInfoLookupYn,
               tlak.applyLabelYn     AS ApplyLabelYn,
               tlak.releaseLabelYn   AS ReleaseLabelYn,
               tlak.encryptionFileYn AS EncryptionFileYn,
               tlak.decryptionFileYn AS DecryptionFileYn 
          FROM (SELECT * FROM TB_LINKED_SERVER where SystemId = @systemId AND UseYn = 1) tls 
          JOIN (SELECT * FROM TB_LINKED_API_KEY WHERE UseYn = 1) tlak 
            ON tls.ServerId = tlak.ServerId
        ) A
  WHERE RowNum BETWEEN @startRow AND @endRow