Storage Layout

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Version: 7.0

Data Types

  • Num: compressed integer (1-5 bytes)
  • Token: length (Num) and bytes of UTF8 byte representation
  • double: number, stored as token
  • boolean: boolean (1 byte, 00 or 01)

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 discarded
2.6. 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()