Category Archives: Uncategorized

(Originally posted 2006-11-08.) Well, I don’t know about that. Maybe this contribution to the debate won’t add much. But there must be at least one performance person out there who hasn’t heard of the discussion around RMPTTOM. But would I want such a person amongst my readership? 🙂 I’m not going to rehearse the wholeContinue reading “Better Late Then Never – RMPTTOM”

(Originally posted 2006-05-22.) Here are a couple more SQL processing APARs. APAR PK22814 for Version 8 ESTIMATED SUBQUERY COST IS TOO HIGH WITH SORT MERGE JOIN. The APAR text says Correlated subquery cost is over-estimated for sort merge join. A well-performing sort merge join plan might not be chosen by DB2. Correlated subquery cost canContinue reading “2 More DB2 Access Path APARS”

(Originally posted 2006-05-15.) DB2 Version 8 introduced some very significant exploitation of 64-bit virtual storage. It would be naive to believe that was a total conversion to 64-bit and indeed installations’ mileage varies, depending on circumstances. Here are two APARs that show the journey continues… PK21268 MOVE CURRENT PATH STORAGE OUT OF STACK AND INTOContinue reading “DB2 Virtual Storage – The Journey Continues”

(Originally posted 2006-05-13.) (Scroll down if you’re not interested in DB2) This past week I’ve been updating our SQL Analysis code to cope with Unicode SQL statements. (If you bind a package or plan once you’ve gone to DB2 Version 8 New Function Mode the statement text is stored in the Catalog in Unicode.) TheseContinue reading “ASCII to EBCDIC Conversion with DFSORT”

(Originally posted 2006-05-06.) Nope, I’m not going to do a Rumsfeld. 🙂 But there are a couple of things I didn’t know (I didn’t know) about DFSORT. Relating them to you is probably OK because It’s not something I’m embarrassed about.:-) If you want to understand some of the funkier new DFSORT tricks you probablyContinue reading “Unknown Unknowns”

(Originally posted 2006-05-02.) Saw an APAR described as INCORRECT OUPUT 🙂 the other day. That reminds me of a time long ago when a friend had a foil titled Qualtiy.:-)

(Originally posted 2006-04-25.) Following on from Generating XML Using DFSORT – Part II here are some thoughts on how to parse XML with DFSORT. NOTE: For more complex XML than this entry describes you probably want to use the XML Toolkit for z/OS. This provides C++ and Java parsers for XML and a stand-alone XSLTContinue reading “Parsing XML with DFSORT”

(Originally posted 2006-04-24.) In Generating XML Using DFSORT – Part I I described how to generate XML using some of DFSORT’s new features. But the XML we generated was only one of the possible styles of XML: Most of the information was specified as attributes (with the values enclosed in quotes). Here’s a sample line:Continue reading “Generating XML Using DFSORT – Part II”

(Originally posted 2006-04-24.) Following on from This entry on creating CSV files here’s the first of several entries on manipulating XML with DFSORT… This is not intended to be a tutorial on XML but rather an exploration of how DFSORT can read (shred) and write (compose) XML. (I also use the terms ingest and emitContinue reading “Generating XML Using DFSORT – Part I”

(Originally posted 2006-04-21.) I plan on writing some entries on creating and parsing XML with DFSORT (using the UK90006 / UK90007 functional enhancments that DFSORT Development recently announced). But here’s a limbering up example – creating a CSV file from regular sequential file input. CSV files (Comma-Separated Value (or Variable if you prefer)) are ofContinue reading “Using DFSORT to create CSV files”