SQL Server Query - Which is better in performance?
<p>I think query 1 is more readable than query 2, but I'd like to know if there is any difference between them in terms of performance?</p>

<p>Query 1</p>

<pre><code>UPDATE table_1
SET col_1 = 
      CASE WHEN table_1.col_pk IS NULL THEN value1
           ELSE value2
      END
FROM table_1
LEFT JOIN table_2 ON table_1.col_pk = table_2.col_pk
</code></pre>

<p>or</p>

<p>Query 2</p>

<pre><code>UPDATE table_1
SET col_1 = value1
FROM table_1
LEFT JOIN table_2 ON table_1.col_pk = table_2.col_pk
WHERE table_1.col_pk IS NULL

UPDATE table_1
SET col_1 = value2
FROM table_1
INNER JOIN table_2 ON table_1.col_pk = table_2.col_pk
</code></pre>