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    <p>As indicated by <a href="https://stackoverflow.com/questions/14989008/do-update-statements-set-all-values-concurrently-at-the-same-time#comment21051031_14989008">Joe's SQL Fiddle comment</a>, it does indeed matter what order the column updates are performed. The MySQL documentation for <a href="http://dev.mysql.com/doc/refman/5.0/en/update.html" rel="nofollow noreferrer"><code>UPDATE</code></a> indicates this, stating that the expression for each column update will be evaluated in the order declared, and it always uses the "current" value of a column:</p> <blockquote> <p>If you access a column from the table to be updated in an expression, <code>UPDATE</code> uses the current value of the column. For example, the following statement sets <code>col1</code> to one more than its current value:</p> <pre><code>UPDATE t1 SET col1 = col1 + 1; </code></pre> <p>The second assignment in the following statement sets <code>col2</code> to the current (updated) <code>col1</code> value, not the original <code>col1</code> value. The result is that <code>col1</code> and <code>col2</code> have the same value. This behavior differs from standard SQL.</p> <pre><code>UPDATE t1 SET col1 = col1 + 1, col2 = col1; </code></pre> <p>Single-table UPDATE assignments are generally evaluated from left to right. For multiple-table updates, there is no guarantee that assignments are carried out in any particular order.</p> </blockquote> <p>So for <code>UPDATE var SET foo=foo+1, bar=foo+1</code>, <code>foo</code> will be set to <code>foo+1</code>, then the <code>bar</code> update will use the newly set value of <code>foo</code> in <code>foo+1</code>.</p> <p>It may also be worthwhile to note that this behavior differs from the SQL standard, which indicates that all column updates should conceptually happen "at the same time".</p>
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Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

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