pgsql.php

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    }

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

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

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

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

    // }}}
    // {{{ 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) {
            // (disabled) hack to shut up error messages from libpq.a
            //@fclose(@fopen("php://stderr", "w"));
            $result = @pg_exec($this->connection, 'end;');
            $this->transaction_opcount = 0;
            if (!$result) {
                return $this->pgsqlRaiseError();
            }
        }
        return DB_OK;
    }

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

    /**
     * Roll back (undo) the current transaction.
     */
    function rollback()
    {
        if ($this->transaction_opcount > 0) {
            $result = @pg_exec($this->connection, 'abort;');
            $this->transaction_opcount = 0;
            if (!$result) {
                return $this->pgsqlRaiseError();
            }
        }
        return DB_OK;
    }

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

    /**
     * Gets the number of rows affected by the last query.
     * if the last query was a select, returns 0.
     *
     * @return int number of rows affected by the last query or DB_ERROR
     */
    function affectedRows()
    {
        return $this->affected;
    }

    // }}}
    // {{{ 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);
        $repeat = false;
        do {
            $this->pushErrorHandling(PEAR_ERROR_RETURN);
            $result =& $this->query("SELECT NEXTVAL('${seqname}')");
            $this->popErrorHandling();
            if ($ondemand && DB::isError($result) &&
                $result->getCode() == DB_ERROR_NOSUCHTABLE) {
                $repeat = true;
                $this->pushErrorHandling(PEAR_ERROR_RETURN);
                $result = $this->createSequence($seq_name);
                $this->popErrorHandling();
                if (DB::isError($result)) {
                    return $this->raiseError($result);
                }
            } else {
                $repeat = false;
            }
        } while ($repeat);
        if (DB::isError($result)) {
            return $this->raiseError($result);
        }
        $arr = $result->fetchRow(DB_FETCHMODE_ORDERED);
        $result->free();
        return $arr[0];
    }

    // }}}
    // {{{ createSequence()

    /**
     * Create the sequence
     *
     * @param string $seq_name the name of the sequence
     * @return mixed DB_OK on success or DB error on error
     * @access public
     */
    function createSequence($seq_name)
    {
        $seqname = $this->getSequenceName($seq_name);
        $result = $this->query("CREATE SEQUENCE ${seqname}");
        return $result;
    }

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

    /**
     * Drop a sequence
     *
     * @param string $seq_name the name of the sequence
     * @return mixed DB_OK on success or DB error on error
     * @access public
     */
    function dropSequence($seq_name)
    {
        $seqname = $this->getSequenceName($seq_name);
        return $this->query("DROP SEQUENCE ${seqname}");
    }

    // }}}
    // {{{ modifyLimitQuery()

    function modifyLimitQuery($query, $from, $count, $params = array())
    {
        $query = $query . " LIMIT $count OFFSET $from";
        return $query;
    }

    // }}}
    // {{{ pgsqlRaiseError()

    /**
     * Gather information about an error, then use that info to create a
     * DB error object and finally return that object.
     *
     * @param  integer  $errno  PEAR error number (usually a DB constant) if
     *                          manually raising an error
     * @return object  DB error object
     * @see errorNative()
     * @see errorCode()
     * @see DB_common::raiseError()
     */
    function pgsqlRaiseError($errno = null)
    {
        $native = $this->errorNative();
        if ($errno === null) {
            $err = $this->errorCode($native);
        } else {
            $err = $errno;
        }
        return $this->raiseError($err, null, null, null, $native);
    }

    // }}}
    // {{{ _pgFieldFlags()

    /**
     * Flags of a Field
     *
     * @param int $resource PostgreSQL result identifier
     * @param int $num_field the field number
     *
     * @return string The flags of the field ("not_null", "default_value",
     *                "primary_key", "unique_key" and "multiple_key"
     *                are supported).  The default value is passed
     *                through rawurlencode() in case there are spaces in it.
     * @access private
     */
    function _pgFieldFlags($resource, $num_field, $table_name)
    {
        $field_name = @pg_fieldname($resource, $num_field);

        $result = @pg_exec($this->connection, "SELECT f.attnotnull, f.atthasdef
                                FROM pg_attribute f, pg_class tab, pg_type typ
                                WHERE tab.relname = typ.typname
                                AND typ.typrelid = f.attrelid
                                AND f.attname = '$field_name'
                                AND tab.relname = '$table_name'");
        if (@pg_numrows($result) > 0) {
            $row = @pg_fetch_row($result, 0);
            $flags  = ($row[0] == 't') ? 'not_null ' : '';

            if ($row[1] == 't') {
                $result = @pg_exec($this->connection, "SELECT a.adsrc
                                    FROM pg_attribute f, pg_class tab, pg_type typ, pg_attrdef a
                                    WHERE tab.relname = typ.typname AND typ.typrelid = f.attrelid
                                    AND f.attrelid = a.adrelid AND f.attname = '$field_name'
                                    AND tab.relname = '$table_name' AND f.attnum = a.adnum");
                $row = @pg_fetch_row($result, 0);
                $num = preg_replace("/'(.*)'::\w+/", "\\1", $row[0]);
                $flags .= 'default_' . rawurlencode($num) . ' ';
            }
        } else {
            $flags = '';
        }
        $result = @pg_exec($this->connection, "SELECT i.indisunique, i.indisprimary, i.indkey
                                FROM pg_attribute f, pg_class tab, pg_type typ, pg_index i
                                WHERE tab.relname = typ.typname
                                AND typ.typrelid = f.attrelid
                                AND f.attrelid = i.indrelid
                                AND f.attname = '$field_name'
                                AND tab.relname = '$table_name'");
        $count = @pg_numrows($result);

        for ($i = 0; $i < $count ; $i++) {
            $row = @pg_fetch_row($result, $i);
            $keys = explode(' ', $row[2]);

            if (in_array($num_field + 1, $keys)) {
                $flags .= ($row[0] == 't' && $row[1] == 'f') ? 'unique_key ' : '';
                $flags .= ($row[1] == 't') ? 'primary_key ' : '';
                if (count($keys) > 1)
                    $flags .= 'multiple_key ';
            }
        }

        return trim($flags);
    }

    // }}}
    // {{{ tableInfo()

    /**
     * Returns information about a table or a result set.
     *
     * NOTE: only supports 'table' and 'flags' if <var>$result</var>
     * is a table name.
     *
     * @param object|string  $result  DB_result object from a query or a
     *                                string containing the name of a table
     * @param int            $mode    a valid tableInfo mode
     * @return array  an associative array with the information requested
     *                or an error object if something is wrong
     * @access public
     * @internal
     * @see DB_common::tableInfo()
     */
    function tableInfo($result, $mode = null)
    {
        if (isset($result->result)) {
            /*
             * Probably received a result object.
             * Extract the result resource identifier.
             */
            $id = $result->result;
            $got_string = false;
        } elseif (is_string($result)) {
            /*
             * Probably received a table name.
             * Create a result resource identifier.
             */
            $id = @pg_exec($this->connection, "SELECT * FROM $result LIMIT 0");
            $got_string = true;
        } else {
            /*
             * Probably received a result resource identifier.
             * Copy it.
             * Deprecated.  Here for compatibility only.
             */
            $id = $result;
            $got_string = false;
        }

        if (!is_resource($id)) {
            return $this->pgsqlRaiseError(DB_ERROR_NEED_MORE_DATA);
        }

        if ($this->options['portability'] & DB_PORTABILITY_LOWERCASE) {
            $case_func = 'strtolower';
        } else {
            $case_func = 'strval';
        }

        $count = @pg_numfields($id);

        // made this IF due to performance (one if is faster than $count if's)
        if (!$mode) {

            for ($i=0; $i<$count; $i++) {
                $res[$i]['table'] = $got_string ? $case_func($result) : '';
                $res[$i]['name']  = $case_func(@pg_fieldname($id, $i));
                $res[$i]['type']  = @pg_fieldtype($id, $i);
                $res[$i]['len']   = @pg_fieldsize($id, $i);
                $res[$i]['flags'] = $got_string ? $this->_pgFieldflags($id, $i, $result) : '';
            }

        } else { // full
            $res['num_fields']= $count;

            for ($i=0; $i<$count; $i++) {
                $res[$i]['table'] = $got_string ? $case_func($result) : '';
                $res[$i]['name']  = $case_func(@pg_fieldname($id, $i));
                $res[$i]['type']  = @pg_fieldtype($id, $i);
                $res[$i]['len']   = @pg_fieldsize($id, $i);
                $res[$i]['flags'] = $got_string ? $this->_pgFieldFlags($id, $i, $result) : '';

                if ($mode & DB_TABLEINFO_ORDER) {
                    $res['order'][$res[$i]['name']] = $i;
                }
                if ($mode & DB_TABLEINFO_ORDERTABLE) {
                    $res['ordertable'][$res[$i]['table']][$res[$i]['name']] = $i;
                }
            }
        }

        // free the result only if we were called on a table
        if ($got_string) {
            @pg_freeresult($id);
        }
        return $res;
    }

    // }}}
    // {{{ getTablesQuery()

    /**
     * Returns the query needed to get some backend info
     * @param string $type What kind of info you want to retrieve
     * @return string The SQL query string
     */
    function getSpecialQuery($type)
    {
        switch ($type) {
            case 'tables':
                return "SELECT c.relname as \"Name\"
                        FROM pg_class c, pg_user u
                        WHERE c.relowner = u.usesysid AND c.relkind = 'r'
                        AND not exists (select 1 from pg_views where viewname = c.relname)
                        AND c.relname !~ '^(pg_|sql_)'
                        UNION
                        SELECT c.relname as \"Name\"
                        FROM pg_class c
                        WHERE c.relkind = 'r'
                        AND not exists (select 1 from pg_views where viewname = c.relname)
                        AND not exists (select 1 from pg_user where usesysid = c.relowner)
                        AND c.relname !~ '^pg_'";
            case 'views':
                // Table cols: viewname | viewowner | definition
                return 'SELECT viewname FROM pg_views';
            case 'users':
                // cols: usename |usesysid|usecreatedb|usetrace|usesuper|usecatupd|passwd  |valuntil
                return 'SELECT usename FROM pg_user';
            case 'databases':
                return 'SELECT datname FROM pg_database';
            case 'functions':
                return 'SELECT proname FROM pg_proc';
            default:
                return null;
        }
    }

    // }}}

}

/*
 * Local variables:
 * tab-width: 4
 * c-basic-offset: 4
 * End:
 */

?>