obsidian-bases: Obsidian's Database Layer

Obsidian Bases (launched 2025) turns vault notes into queryable, dynamic views. Tables, cards, lists, maps. Defined in .base files. No plugin required; it is a core Obsidian feature.

Substrate preference (v1.7+): This skill is a self-contained fallback. Prefer `kepano/obsidian-skills` as the authoritative substrate — its obsidian-bases skill is the canonical reference for Bases YAML, formulas, and view definitions. If you see an obsidian-bases skill available without the claude-obsidian: namespace, that is kepano's version: use it. The reference below is provided so the plugin remains functional when kepano's marketplace is not installed. Install: claude plugin marketplace add kepano/obsidian-skills. Official Bases docs: https://help.obsidian.md/bases/syntax

File Format

.base files contain valid YAML. The root keys are filters, formulas, properties, summaries, and views.

# Global filters: apply to ALL views
filters:
  and:
    - file.hasTag("wiki")
    - 'status != "archived"'

# Computed properties
formulas:
  age_days: '(now() - file.ctime).days.round(0)'
  status_icon: 'if(status == "mature", "✅", "🔄")'

# Display name overrides for properties panel
properties:
  status:
    displayName: "Status"
  formula.age_days:
    displayName: "Age (days)"

# One or more views
views:
  - type: table
    name: "All Pages"
    order:
      - file.name
      - type
      - status
      - updated
      - formula.age_days

Filters

Filters select which notes appear. Applied globally or per-view.

# Single string filter
filters: 'status == "current"'

# AND: all must be true
filters:
  and:
    - 'status != "archived"'
    - file.hasTag("wiki")

# OR: any can be true
filters:
  or:
    - file.hasTag("concept")
    - file.hasTag("entity")

# NOT: exclude matches
filters:
  not:
    - file.inFolder("wiki/meta")

# Nested
filters:
  and:
    - file.inFolder("wiki/")
    - or:
        - 'type == "concept"'
        - 'type == "entity"'

Filter operators

== != > < >= <=

Useful filter functions

Properties

Three types:

• Note properties: from frontmatter: status, type, updated
• File properties: metadata: file.name, file.mtime, file.size, file.ctime, file.tags, file.folder
• Formula properties: computed: formula.age_days

Formulas

Defined in formulas:. Referenced as formula.name in order: and properties:.

formulas:
  # Days since created
  age_days: '(now() - file.ctime).days.round(0)'

  # Days until a date property
  days_until: 'if(due_date, (date(due_date) - today()).days, "")'

  # Conditional label
  status_icon: 'if(status == "mature", "✅", if(status == "developing", "🔄", "🌱"))'

  # Word count estimate
  word_est: '(file.size / 5).round(0)'

Key rule: Subtracting two dates returns a Duration. Not a number. Always access .days first:

# CORRECT
age: '(now() - file.ctime).days'

# WRONG: crashes
age: '(now() - file.ctime).round(0)'

Always guard nullable properties with `if()`:

# CORRECT
days_left: 'if(due_date, (date(due_date) - today()).days, "")'

View Types

Table

views:
  - type: table
    name: "Wiki Index"
    limit: 100
    order:
      - file.name
      - type
      - status
      - updated
    groupBy:
      property: type
      direction: ASC

Cards

views:
  - type: cards
    name: "Gallery"
    order:
      - file.name
      - tags
      - status

List

views:
  - type: list
    name: "Quick List"
    order:
      - file.name
      - status

Wiki Vault Templates

Wiki content dashboard (all non-meta pages)

filters:
  and:
    - file.inFolder("wiki/")
    - not:
        - file.inFolder("wiki/meta")

formulas:
  age: '(now() - file.ctime).days.round(0)'

properties:
  formula.age:
    displayName: "Age (days)"

views:
  - type: table
    name: "All Wiki Pages"
    order:
      - file.name
      - type
      - status
      - updated
      - formula.age
    groupBy:
      property: type
      direction: ASC

Entity index (people, orgs, repos)

filters:
  and:
    - file.inFolder("wiki/entities/")
    - 'file.ext == "md"'

views:
  - type: table
    name: "Entities"
    order:
      - file.name
      - entity_type
      - status
      - updated
    groupBy:
      property: entity_type
      direction: ASC

Recent ingests

filters:
  and:
    - file.inFolder("wiki/sources/")

views:
  - type: table
    name: "Sources"
    order:
      - file.name
      - source_type
      - created
      - status
    groupBy:
      property: source_type
      direction: ASC

Embedding in Notes

![[MyBase.base]]

![[MyBase.base#View Name]]

Where to Save

Store .base files in wiki/meta/ for vault dashboards:

• wiki/meta/dashboard.base: main content view
• wiki/meta/entities.base: entity tracker
• wiki/meta/sources.base: ingestion log

YAML Quoting Rules

• Formulas with double quotes → wrap in single quotes: 'if(done, "Yes", "No")'
• Strings with colons or special chars → wrap in double quotes: "Status: Active"
• Unquoted strings with : break YAML parsing

What Not to Do

• Do not use from: or where:: those are Dataview syntax, not Obsidian Bases
• Do not use sort: at the root level: sorting is per-view via order: and groupBy:
• Do not put .base files outside the vault: they only render inside Obsidian
• Do not reference formula.X in order: without defining X in formulas:

How to think (10-principle mapping)

When working on this skill, apply the 10-principle loop. See skills/think/SKILL.md for the canonical framework.