mysqli.php

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     * @param int      $fetchmode how the resulting array should be indexed
     * @param int      $rownum    the row number to fetch
     *
     * @return mixed DB_OK on success, null when end of result set is
     *               reached or on failure
     *
     * @see DB_result::fetchInto()
     * @access private
     */
    function fetchInto($result, &$arr, $fetchmode, $rownum=null)
    {
        if ($rownum !== null) {
            if (!@mysqli_data_seek($result, $rownum)) {
                return null;
            }
        }
        if ($fetchmode & DB_FETCHMODE_ASSOC) {
            $arr = @mysqli_fetch_array($result, MYSQLI_ASSOC);
            if ($this->options['portability'] & DB_PORTABILITY_LOWERCASE && $arr) {
                $arr = array_change_key_case($arr, CASE_LOWER);
            }
        } else {
            $arr = @mysqli_fetch_row($result);
        }
        if (!$arr) {
            $errno = @mysqli_errno($this->connection);
            if (!$errno) {
                return null;
            }
            return $this->mysqlRaiseError($errno);
        }
        if ($this->options['portability'] & DB_PORTABILITY_RTRIM) {
            /*
             * Even though this DBMS already trims output, we do this because
             * a field might have intentional whitespace at the end that
             * gets removed by DB_PORTABILITY_RTRIM under another driver.
             */
            $this->_rtrimArrayValues($arr);
        }
        if ($this->options['portability'] & DB_PORTABILITY_NULL_TO_EMPTY) {
            $this->_convertNullArrayValuesToEmpty($arr);
        }
        return DB_OK;
    }

    // }}}
    // {{{ freeResult()

    /**
     * Free the internal resources associated with $result.
     *
     * @param resource $result MySQL result identifier
     * @return bool true on success, false if $result is invalid
     * @access public
     */
    function freeResult($result)
    {
# need to come up with different means for next line
# since $result is object (int)$result won't fly...
//        unset($this->num_rows[(int)$result]);
        return @mysqli_free_result($result);
    }

    // }}}
    // {{{ numCols()

    /**
     * Get the number of columns in a result set.
     *
     * @param $result MySQL result identifier
     *
     * @access public
     *
     * @return int the number of columns per row in $result
     */
    function numCols($result)
    {
        $cols = @mysqli_num_fields($result);

        if (!$cols) {
            return $this->mysqlRaiseError();
        }

        return $cols;
    }

    // }}}
    // {{{ numRows()

    /**
     * Get the number of rows in a result set.
     *
     * @param resource $result MySQL result identifier
     * @return int the number of rows in $result
     * @access public
     */
    function numRows($result)
    {
        $rows = @mysqli_num_rows($result);
        if ($rows === null) {
            return $this->mysqlRaiseError();
        }
        return $rows;
    }

    // }}}
    // {{{ autoCommit()

    /**
     * Enable/disable automatic commits.
     */
    function autoCommit($onoff = false)
    {
        // XXX if $this->transaction_opcount > 0, we should probably
        // issue a warning here.
        $this->autocommit = $onoff ? true : false;
        return DB_OK;
    }

    // }}}
    // {{{ commit()

    /**
     * Commit the current transaction.
     */
    function commit()
    {
        if ($this->transaction_opcount > 0) {
            if ($this->_db) {
                if (!@mysqli_select_db($this->connection, $this->_db)) {
                    return $this->mysqlRaiseError(DB_ERROR_NODBSELECTED);
                }
            }
            $result = @mysqli_query($this->connection, 'COMMIT');
            $result = @mysqli_query($this->connection, 'SET AUTOCOMMIT=1');
            $this->transaction_opcount = 0;
            if (!$result) {
                return $this->mysqlRaiseError();
            }
        }
        return DB_OK;
    }

    // }}}
    // {{{ rollback()

    /**
     * Roll back (undo) the current transaction.
     */
    function rollback()
    {
        if ($this->transaction_opcount > 0) {
            if ($this->_db) {
                if (!@mysqli_select_db($this->connection, $this->_db)) {
                    return $this->mysqlRaiseError(DB_ERROR_NODBSELECTED);
                }
            }
            $result = @mysqli_query($this->connection, 'ROLLBACK');
            $result = @mysqli_query($this->connection, 'SET AUTOCOMMIT=1');
            $this->transaction_opcount = 0;
            if (!$result) {
                return $this->mysqlRaiseError();
            }
        }
        return DB_OK;
    }

    // }}}
    // {{{ affectedRows()

    /**
     * Gets the number of rows affected by the data manipulation
     * query.  For other queries, this function returns 0.
     *
     * @return integer number of rows affected by the last query
     */
    function affectedRows()
    {
        if (DB::isManip($this->last_query)) {
            return @mysqli_affected_rows($this->connection);
        } else {
            return 0;
        }
     }

    // }}}
    // {{{ errorNative()

    /**
     * Get the native error code of the last error (if any) that
     * occured on the current connection.
     *
     * @return int native MySQL error code
     * @access public
     */
    function errorNative()
    {
        return @mysqli_errno($this->connection);
    }

    // }}}
    // {{{ nextId()

    /**
     * Returns the next free id in a sequence
     *
     * @param string  $seq_name  name of the sequence
     * @param boolean $ondemand  when true, the seqence is automatically
     *                           created if it does not exist
     *
     * @return int  the next id number in the sequence.  DB_Error if problem.
     *
     * @internal
     * @see DB_common::nextID()
     * @access public
     */
    function nextId($seq_name, $ondemand = true)
    {
        $seqname = $this->getSequenceName($seq_name);
        do {
            $repeat = 0;
            $this->pushErrorHandling(PEAR_ERROR_RETURN);
            $result = $this->query("UPDATE ${seqname} ".
                                   'SET id=LAST_INSERT_ID(id+1)');
            $this->popErrorHandling();
            if ($result === DB_OK) {
                /** COMMON CASE **/
                $id = @mysqli_insert_id($this->connection);
                if ($id != 0) {
                    return $id;
                }
                /** EMPTY SEQ TABLE **/
                // Sequence table must be empty for some reason, so fill it and return 1
                // Obtain a user-level lock
                $result = $this->getOne("SELECT GET_LOCK('${seqname}_lock',10)");
                if (DB::isError($result)) {
                    return $this->raiseError($result);
                }
                if ($result == 0) {
                    // Failed to get the lock, bail with a DB_ERROR_NOT_LOCKED error
                    return $this->mysqlRaiseError(DB_ERROR_NOT_LOCKED);
                }

                // add the default value
                $result = $this->query("REPLACE INTO ${seqname} (id) VALUES (0)");
                if (DB::isError($result)) {
                    return $this->raiseError($result);
                }

                // Release the lock
                $result = $this->getOne("SELECT RELEASE_LOCK('${seqname}_lock')");
                if (DB::isError($result)) {
                    return $this->raiseError($result);
                }
                // We know what the result will be, so no need to try again
                return 1;

            /** ONDEMAND TABLE CREATION **/
            } elseif ($ondemand && DB::isError($result) &&
                $result->getCode() == DB_ERROR_NOSUCHTABLE)
            {
                $result = $this->createSequence($seq_name);
                // Since createSequence initializes the ID to be 1,
                // we do not need to retrieve the ID again (or we will get 2)
                if (DB::isError($result)) {
                    return $this->raiseError($result);
                } else {
                    // First ID of a newly created sequence is 1
                    return 1;
                }

            /** BACKWARDS COMPAT **/
            } elseif (DB::isError($result) &&
                      $result->getCode() == DB_ERROR_ALREADY_EXISTS)
            {
                // see _BCsequence() comment
                $result = $this->_BCsequence($seqname);
                if (DB::isError($result)) {
                    return $this->raiseError($result);
                }
                $repeat = 1;
            }
        } while ($repeat);

        return $this->raiseError($result);
    }

    /**
     * Creates a new sequence
     *
     * @param string $seq_name  name of the new sequence
     *
     * @return int  DB_OK on success.  A DB_Error object is returned if
     *              problems arise.
     *
     * @internal
     * @see DB_common::createSequence()
     * @access public
     */
    function createSequence($seq_name)
    {
        $seqname = $this->getSequenceName($seq_name);
        $res = $this->query("CREATE TABLE ${seqname} ".
                            '(id INTEGER UNSIGNED AUTO_INCREMENT NOT NULL,'.
                            ' PRIMARY KEY(id))');
        if (DB::isError($res)) {
            return $res;
        }
        // insert yields value 1, nextId call will generate ID 2
        return $this->query("INSERT INTO ${seqname} (id) VALUES (0)");
    }

    // }}}
    // {{{ dropSequence()

    /**
     * Deletes a sequence
     *
     * @param string $seq_name  name of the sequence to be deleted
     *
     * @return int  DB_OK on success.  DB_Error if problems.