Version

Argent Advanced Technology 1307-A and above

Date

Monday, 17 Jun 2013

Summary

Argent Advanced Technology has been enhanced with ‘Soft Parse Ratio Rules‘ in Argent for Oracle to calculate the ratio of soft parses to hard parses

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Example :

‘Soft Parse Ratio Rules‘ are to calculate the ratio of Soft Parses (SQL is already in library cache) to Hard Parses (SQL must be parsed, validated, and an execution plan formed).
Rule ‘SOFT_PARSE_RATIO_PCT_ACCEPTABLE_OPERATION‘ is broken if the Soft Parse ratio is greater than 80%

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Technical Background

All Oracle SQL statements must be parsed the first time that they execute, and parsing involves a syntax check, a semantic check (against the dictionary), the creation of a decision tree, and the generation of the lowest cost execution plan. Once the execution plan is created, it is stored in the library cache (part of the shared_pool_size) to facilitate re-execution

There are two types of parses, Hard parse and Soft parse

The Soft Parse Ratio Oracle metric is the ratio of soft parses (SQL is already in library cache) to hard parses (SQL must be parsed, validated, and an execution plan formed)

Resolution

N/A