Adaptive Server IQ 12.4.0

Recommended index types

9.2.12 Recommended index types

In the Adaptive Server IQ Administration and Performance Guide, Chapter 4, “Adaptive Server IQ Indexes,” in Table 1–2, Query type/index, the recommended index types for COUNT and range predicate are incorrect. The correct types are:

Type of Query Usage

Recommended Index Type

 

 

As COUNT argument

LF or HG

 

 

In range predicate in WHERE clause (>,

LF or HNG

<, >=, <=, BETWEEN

 

 

 

Note While HNG is recommended, in certain cases LF or HG is faster, and is often used in place of HNG. HNG tends to give consistent performance, while the performance of LF or HG with ranges depends on the size of the range selected.

9.2.13 Changes to “Using join indexes”

The section “Using join indexes” in the Adaptive Server IQ Administration and Performance Guide, Chapter 4, “Adaptive Server IQ Indexes, has several errors, described below.

Privileges needed to create a join index

The book states that you must be the owner of a table or the DBA to create, alter, or synchronize a join index that includes that table.

If you are not the DBA, you need to be owner of the table and have

RESOURCE authority in order to create a join index.

One-to-many relationship

The following changes apply to the subsection “One-to-many relationship.”

The first sentence of the third paragraph should read, “If the join column is made up of more than one column, the combination of the values must be unique on the “one” side.

The example described in the third and fourth paragraphs is changed to match the asiqdemo database, and include sample rows that were omitted. The warning that follows these paragraphs is also changed. The corrected paragraphs read as follows:

Release Bulletin for Digital UNIX

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Sybase IQ 12.4.0 installation instructions Changes to Using join indexes, Adaptive Server IQ Recommended index types