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Use the term "radix tree" instead of "suffix tree" for SP-GiST text opclass.

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What we have implemented is a radix tree (or a radix trie or a patricia
trie), but the docs and code comments incorrectly called it a "suffix tree".

Alexander Korotkov
This commit is contained in:
Heikki Linnakangas
2013-05-08 14:29:28 +03:00
parent 20c00ca668
commit cb953d8b1b
9 changed files with 201 additions and 201 deletions
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10
doc/src/sgml/spgist.sgml
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@ -15,7 +15,7 @@
<acronym>SP-GiST</acronym> is an abbreviation for space-partitioned
<acronym>GiST</acronym>. <acronym>SP-GiST</acronym> supports partitioned
search trees, which facilitate development of a wide range of different
non-balanced data structures, such as quad-trees, k-d trees, and suffix
non-balanced data structures, such as quad-trees, k-d trees, and radix
trees (tries). The common feature of these structures is that they
repeatedly divide the search space into partitions that need not be
of equal size. Searches that are well matched to the partitioning rule
@ -81,9 +81,9 @@
A node contains a downlink that leads to either another, lower-level inner
tuple, or a short list of leaf tuples that all lie on the same index page.
Each node has a <firstterm>label</> that describes it; for example,
in a suffix tree the node label could be the next character of the string
in a radix tree the node label could be the next character of the string
value. Optionally, an inner tuple can have a <firstterm>prefix</> value
that describes all its members. In a suffix tree this could be the common
that describes all its members. In a radix tree this could be the common
prefix of the represented strings. The prefix value is not necessarily
really a prefix, but can be any data needed by the operator class;
for example, in a quad-tree it can store the central point that the four
@ -636,7 +636,7 @@ typedef struct spgLeafConsistentOut
<para>
Individual leaf tuples and inner tuples must fit on a single index page
(8KB by default). Therefore, when indexing values of variable-length
data types, long values can only be supported by methods such as suffix
data types, long values can only be supported by methods such as radix
trees, in which each level of the tree includes a prefix that is short
enough to fit on a page, and the final leaf level includes a suffix also
short enough to fit on a page. The operator class should set
@ -740,7 +740,7 @@ typedef struct spgLeafConsistentOut
<para>
The <productname>PostgreSQL</productname> source distribution includes
several examples of index operator classes for
<acronym>SP-GiST</acronym>. The core system currently provides suffix
<acronym>SP-GiST</acronym>. The core system currently provides radix
trees over text columns and two types of trees over points: quad-tree and
k-d tree. Look into <filename>src/backend/access/spgist/</> to see the
code.