reference/pdo/pdostatement/rowcount.xml
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28529d3539b850e870e3aa97570f4db0e53daa03
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<?xml version="1.0" encoding="UTF-8"?>
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<?xml version="1.0" encoding="utf-8"?>
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<!-- $Revision$ -->
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<refentry xml:id="pdostatement.rowcount" xmlns="http://docbook.org/ns/docbook">
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<refnamediv>
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</refnamediv>
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<refsect1 role="description">
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&reftitle.description;
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<methodsynopsis>
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<type>int</type><methodname>PDOStatement::rowCount</methodname>
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<methodsynopsis role="PDOStatement">
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<modifier>public</modifier> <type>int</type><methodname>PDOStatement::rowCount</methodname>
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<void/>
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</methodsynopsis>
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<para>
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<function>PDOStatement::rowCount</function> returns the number of
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<methodname>PDOStatement::rowCount</methodname> returns the number of
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rows affected by the last DELETE, INSERT, or UPDATE statement
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executed by the corresponding <literal>PDOStatement</literal> object.
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</para>
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<para>
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If the last SQL statement executed by the associated
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<literal>PDOStatement</literal> was a SELECT statement, some databases
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may return the number of rows returned by that statement. However, this
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For statements that produce result sets, such as <literal>SELECT</literal>,
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the behavior is undefined and can be different for each driver.
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Some databases may return the number of rows produced by that statement
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(e.g. MySQL in buffered mode), but this
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behaviour is not guaranteed for all databases and should not be relied
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on for portable applications.
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</para>
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<note>
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<para>
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This method returns "0" (zero) with the SQLite driver at all times,
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and with the PostgreSQL driver only when setting the
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<constant>PDO::ATTR_CURSOR</constant> statement attribute to
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<constant>PDO::CURSOR_SCROLL</constant>.
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</para>
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</note>
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</refsect1>
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<refsect1 role="parameters">
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&reftitle.parameters;
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&no.function.parameters;
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</refsect1>
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<refsect1 role="returnvalues">
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</para>
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</refsect1>
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<refsect1 role="errors">
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&reftitle.errors;
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&pdo.errors;
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</refsect1>
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<refsect1 role="examples">
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&reftitle.examples;
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<para>
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<example>
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<title>Return the number of deleted rows</title>
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<para>
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<function>PDOStatement::rowCount</function> returns the number of
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<methodname>PDOStatement::rowCount</methodname> returns the number of
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rows affected by a DELETE, INSERT, or UPDATE statement.
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</para>
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<programlisting role="php">
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$del->execute();
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/* Return number of rows that were deleted */
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print("Return number of rows that were deleted:\n");
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print "Return number of rows that were deleted:\n";
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$count = $del->rowCount();
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print("Deleted $count rows.\n");
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print "Deleted $count rows.\n";
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?>
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]]>
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</programlisting>
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&example.outputs;
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&example.outputs.similar;
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<screen>
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<![CDATA[
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Return number of rows that were deleted:
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<example>
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<title>Counting rows returned by a SELECT statement</title>
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<para>
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For most databases, <function>PDOStatement::rowCount</function> does not
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For most databases, <methodname>PDOStatement::rowCount</methodname> does not
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return the number of rows affected by a SELECT statement. Instead, use
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<function>PDO::query</function> to issue a SELECT COUNT(*) statement
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<methodname>PDO::query</methodname> to issue a SELECT COUNT(*) statement
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with the same predicates as your intended SELECT statement, then use
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<function>PDOStatement::fetchColumn</function> to retrieve the number
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of rows that will be returned. Your application can then perform the
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correct action.
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<methodname>PDOStatement::fetchColumn</methodname> to retrieve the number
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of matching rows.
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</para>
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<programlisting role="php">
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<![CDATA[
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<?php
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$sql = "SELECT COUNT(*) FROM fruit WHERE calories > 100";
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if ($res = $conn->query($sql)) {
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$res = $conn->query($sql);
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$count = $res->fetchColumn();
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/* Check the number of rows that match the SELECT statement */
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if ($res->fetchColumn() > 0) {
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/* Issue the real SELECT statement and work with the results */
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$sql = "SELECT name FROM fruit WHERE calories > 100";
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foreach ($conn->query($sql) as $row) {
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print "Name: " . $row['NAME'] . "\n";
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}
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}
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/* No rows matched -- do something else */
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else {
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print "No rows matched the query.";
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}
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}
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$res = null;
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$conn = null;
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?>
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print "There are " . $count . " matching records.";
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]]>
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</programlisting>
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&example.outputs;
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&example.outputs.similar;
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<screen>
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<![CDATA[
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apple
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banana
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orange
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pear
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There are 2 matching records.
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]]>
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</screen>
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</example>
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&reftitle.seealso;
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<para>
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<simplelist>
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<member><function>PDOStatement::columnCount</function></member>
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<member><function>PDOStatement::fetchColumn</function></member>
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<member><function>PDO::query</function></member>
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<member><methodname>PDOStatement::columnCount</methodname></member>
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<member><methodname>PDOStatement::fetchColumn</methodname></member>
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<member><methodname>PDO::query</methodname></member>
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</simplelist>
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</para>
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</refsect1>
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</refentry>
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<!-- Keep this comment at the end of the file
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Local variables:
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mode: sgml
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