16f6c0aecf
Inline adoc files when they are included exactly once. Also fix language tags because this inlining gives us better information on what language the code is written in.
40 lines
1.1 KiB
Plaintext
40 lines
1.1 KiB
Plaintext
== Why is this an issue?
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ABAP hints can be used to override the default behavior of the SAP Cost Based Optimizer (CBO). When the execution plan provided by the CBO is not optimal, it is possible to "drive" the CBO by providing the main index to be used to filter rows.
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Such optimizations are not portable from one database to another, such as when migrating from Oracle to DB2. Therefore hard coding an optimization should be done only when it is strongly indicated.
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=== Noncompliant code example
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[source,abap]
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----
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select MY_COLUMN
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into it_data
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from MY_TABLE
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WHERE FILTERING_COLUMN = '0'
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%_HINTS ORACLE 'INDEX("MY_TABLE" "MY_INDEX")'.
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----
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ifdef::env-github,rspecator-view[]
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'''
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== Implementation Specification
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(visible only on this page)
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=== Message
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Make sure this use of %_HINTS is required in this context
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'''
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== Comments And Links
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(visible only on this page)
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=== on 8 Jan 2014, 00:29:22 Ann Campbell wrote:
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Please double-check my compliant solution. I'm guessing that the period at the end of the non-compliant example is a "the select ends here" marker...
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endif::env-github,rspecator-view[]
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