Difference between revisions of "Storage Layout"
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| 1. Flag for path definition (<code>Boolean</code>, always <code>true</code>; legacy)<br/>2. PathNode:<br/>2.1. Name reference (<code>Num</code>)<br/>2.2. Node kind (<code>Num</code>)<br/>2.3. Number of occurrences (<code>Num</code>)<br/>2.4. Number of children (<code>Num</code>)<br/>2.5. <code>Double</code>; legacy, can be reused or discarded<br/>2.6. Recursive generation of child nodes (→ 2)<code> | | 1. Flag for path definition (<code>Boolean</code>, always <code>true</code>; legacy)<br/>2. PathNode:<br/>2.1. Name reference (<code>Num</code>)<br/>2.2. Node kind (<code>Num</code>)<br/>2.3. Number of occurrences (<code>Num</code>)<br/>2.4. Number of children (<code>Num</code>)<br/>2.5. <code>Double</code>; legacy, can be reused or discarded<br/>2.6. Recursive generation of child nodes (→ 2)<code> | ||
| valign='top' | [https://github.com/BaseXdb/basex/blob/master/src/main/java/org/basex/index/path/PathSummary.java PathSummary()]<br/>[https://github.com/BaseXdb/basex/blob/master/src/main/java/org/basex/index/path/PathNode.java PathNode()] | | valign='top' | [https://github.com/BaseXdb/basex/blob/master/src/main/java/org/basex/index/path/PathSummary.java PathSummary()]<br/>[https://github.com/BaseXdb/basex/blob/master/src/main/java/org/basex/index/path/PathNode.java PathNode()] | ||
+ | |- | ||
+ | | valign='top' | '''2.3. Namespaces''' | ||
+ | | 1. Token set, storing prefixes (<code>TokenSet</code>)<br/>2. Token set, storing URIs (<code>TokenSet</code>)<br/>3. NSNode:<br/>3.1. pre value (<code>Num</code>)<br/>3.2. References to prefix/URI pairs (<code>Nums</code>)<br/>3.3. Number of children (<code>Num</code>)<br/>3.4. Recursive generation of child nodes (→ 3)<code> | ||
+ | | valign='top' | [https://github.com/BaseXdb/basex/blob/master/src/main/java/org/basex/data/Namespaces.java Namespaces()]<br/>[https://github.com/BaseXdb/basex/blob/master/src/main/java/org/basex/data/NSNode.java NSNode()] | ||
|} | |} |
Revision as of 17:53, 26 October 2011
Version: 7.0
Data Types
Num
: compressed integer (1-5 bytes)Token
: length (Num
) and bytes of UTF8 byte representationdouble
: number, stored as tokenboolean
: boolean (1 byte,00
or01
)
inf.basex
Description | Format | Method |
---|---|---|
Disk Data | Database meta information | DiskData() |
1. Meta Data | Pairs of key/value tokens, suffixed by empty key: • PERM → User Permissions
|
MetaData.read() Users.read() |
2. Main memory indexes | Pairs of key/value tokens, suffixed by empty key: • TAGS → Tag Index• ATTS → Attribute Index• PATH → Path Index• NS → Namespaces• DOCS → Document Index
|
DiskData() |
2.1. Name Index Element/attribute names |
Token set, enriched with statistical information: 1. Token set: key array ( Tokens ), next/bucket/size arrays (Nums )2. Content kind ( Num )2.1. Number: min/max ( Doubles )2.2. Category: number of entries ( Num ), entries (Tokens )2.3. Number of entries ( Num )2.4. Leaf flag ( Boolean )2.5. Maximum text length ( Double ; legacy, could be Num )
|
Names() TokenSet.read() StatsKey() |
2.2. Path Index | 1. Flag for path definition (Boolean , always true ; legacy)2. PathNode: 2.1. Name reference ( Num )2.2. Node kind ( Num )2.3. Number of occurrences ( Num )2.4. Number of children ( Num )2.5. Double ; legacy, can be reused or discarded2.6. Recursive generation of child nodes (→ 2)
|
PathSummary() PathNode() |
2.3. Namespaces | 1. Token set, storing prefixes (TokenSet )2. Token set, storing URIs ( TokenSet )3. NSNode: 3.1. pre value ( Num )3.2. References to prefix/URI pairs ( Nums )3.3. Number of children ( Num )3.4. Recursive generation of child nodes (→ 3)
|
Namespaces() NSNode() |