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      19.5.1.23 Replication and the Query Optimizer
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   It is possible for the data on the source and replica to become
        different if a statement is written in such a way that the data
        modification is nondeterministic; that is, left up the query
        optimizer. (In general, this is not a good practice, even
        outside of replication.) Examples of nondeterministic statements
        include
   <a class="link" href="delete.html" title="15.2.2 DELETE Statement">
    <code class="literal">
     DELETE
    </code>
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   or
   <a class="link" href="update.html" title="15.2.17 UPDATE Statement">
    <code class="literal">
     UPDATE
    </code>
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   statements that use
   <code class="literal">
    LIMIT
   </code>
   with no
   <code class="literal">
    ORDER BY
   </code>
   clause; see
   <a class="xref" href="replication-features-limit.html" title="19.5.1.18 Replication and LIMIT">
    Section 19.5.1.18, “Replication and LIMIT”
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   , for a
        detailed discussion of these.
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