Indexable and/or stage 1 predicates can be evaluated at the early stage during row retrieval. There are multiple factors that can affect the stage of predicate evaluation, for example, the data type and length of the operands, the syntax of the predicate, the join sequence, etc. This article is focused on how Db2 query optimization can be used to achieve early stage evaluation whenever possible for predicates with DECFLOAT and implicit string to numeric type conversion. This article is about the DECFLOAT function and its performance improvements.
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