title: BEFORE INSERT trigger, ignore certain rows at multiple insertion
body: <p>Given table </p>
  
  <pre><code>CREATE TABLE testtab(
  col  int
  )
  </code></pre>
  
  <p>I need check inserted values and if value meets condition, then ignore these rows. So, trigger looks  something like this:</p>
  
  <pre><code>DELIMITER $$
  CREATE TRIGGER check_rows BEFORE INSERT ON testtab
      FOR EACH ROW 
      BEGIN
          IF new.col &gt; 7 THEN
              -- here need ignore that row and do not insert
          END IF;
      END; $$
  </code></pre>
  
  <p>I can use <code>signal sqlstate '45000'</code> but problem is that when I use multiple insert syntax:</p>
  
  <pre><code>insert into testtab
  values
  (55),
  (4)
  </code></pre>
  
  <p>trigger ignores all rows, but I need ignore just "55", and insert "4".</p>
  
  <p>So, how to ignore certain rows and not all, when use multiple/bulk insert ?</p>