Paul Tuohy
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Guru: Faster Fetching, Revisited
November 13, 2017 Paul Tuohy
While visiting a client recently, I was shown how they were using a multi-row FETCH into a multiple-occurrence data structure to retrieve large sets of data. When I asked why they were not using a data structure array instead, I was referred to an IT Jungle article in which Ted Holt answered a question on whether it was faster to perform a row-at-a-time FETCH or a multi-row FETCH when using embedded SQL.
Ted provided a comparison between a row-at-a-time FETCH, a multi-row FETCH into a data structure array, and a multi-row FETCH into a multiple-occurrence data structure. At the end …
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Handling Constraints Revisited
March 31, 2015 Paul Tuohy
… Read moreI recently had an email from Doug, who was making use of some code I had published way back in February 2010 in my article Handling Constraint Violations in RPG. The article discussed how to trap a constraint violation caused by a WRITE/UPDATE/DELETE operation and, more importantly, how to determine the name of the constraint that caused the violation.
Doug had come up with an instance where my code was not working! After going through the usual stages of denial, anger, and some expensive therapy, I read the rest of the email. Doug’s code worked fine with an RPG
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Handling Constraint Violations in RPG
February 17, 2010 Paul Tuohy
… Read moreConstraints have been around for a long time but have not quite made it into every programmer’s tool kit. This is partly explained by the fact that implementing constraints in an existing application can be tricky–but it doesn’t explain why constraints are not used extensively in new applications.
On a side note, the lack of constraints on a database is one of the reasons I have heard why data should be moved/copied from the i to other database servers, such as SQL server and Oracle, for such things as data warehousing. To a “pure database person,” a lack of constraints