The key point here is that the data format is delimited, and there is a requirement to validate the parsed info set against some rules ( length constraints, in this case). I would - set terminator="/" - set lengthKind='delimited' - use xs:minLength and xs:maxLength facets to check the length ( or use a pattern facet if you must, but min/maxLength facets will use less CPU ) - switch on validation in the DFDL parser so that the length of the delimited value gets checked against the facets in the schema. Other possibilities exist ( e.g. DFDL assert to check the length ) but this is the most efficient. regards, Tim Kimber, IBM Integration Bus Development (Industry Packs) Hursley, UK Internet: kimbert@uk.ibm.com Tel. 01962-816742 Internal tel. 37246742 From: "mfcplus@yahoo.com" <mfcplus@yahoo.com> To: Tim Kimber/UK/IBM@IBMGB, Date: 28/03/2014 11:25 Subject: Re: [DFDL-WG] newbie question a field that is 3-5 chars long alphanumeric, basically a \w{3,5}, it should give out parsing error if it doesnt fit by the pattern, no initiator terminator is / Sent from Yahoo Mail on Android From: Tim Kimber <KIMBERT@uk.ibm.com>; To: <dfdl-wg@ogf.org>; Subject: Re: [DFDL-WG] newbie question Sent: Fri, Mar 28, 2014 10:19:47 AM It depends on the data format. Normally a variable length field is terminated by a delimiter, so a data pattern/regex is not required. Can you describe the format in a little more detail? regards, Tim Kimber, IBM Integration Bus Development (Industry Packs) Hursley, UK Internet: kimbert@uk.ibm.com Tel. 01962-816742 Internal tel. 37246742 From: Bing Lu <mfcplus@yahoo.com> To: "dfdl-wg@ogf.org" <dfdl-wg@ogf.org>, Date: 28/03/2014 03:35 Subject: [DFDL-WG] newbie question Sent by: dfdl-wg-bounces@ogf.org what's the best dfdl approache to describe a variable length alpha numeric field? should i use simpletype restriction pattern, or use dfdl:assert testPattern? thanks in advance-- dfdl-wg mailing list dfdl-wg@ogf.org https://www.ogf.org/mailman/listinfo/dfdl-wg Unless stated otherwise above: IBM United Kingdom Limited - Registered in England and Wales with number 741598. Registered office: PO Box 41, North Harbour, Portsmouth, Hampshire PO6 3AU Unless stated otherwise above: IBM United Kingdom Limited - Registered in England and Wales with number 741598. Registered office: PO Box 41, North Harbour, Portsmouth, Hampshire PO6 3AU