Obsidian Bases

Obsidian Bases Skill

Obsidian Bases are YAML-based .base files that define dynamic views of notes in an Obsidian vault. A Base file can contain multiple views, global filters, formulas, property configurations, and custom summaries.

Complete Schema

# Global filters apply to ALL views in the base
filters:
  and: []    # All conditions must be true
  or: []     # Any condition can be true
  not: []    # Exclude matching items
  # Can also be a single filter string: 'status == "done"'

# Define formula properties (computed values)
formulas:
  formula_name: 'expression'

# Configure display names for properties
properties:
  property_name:
    displayName: "Display Name"
  formula.formula_name:
    displayName: "Formula Display Name"

# Define custom summary formulas
summaries:
  custom_summary_name: 'values.mean().round(3)'

# Define one or more views
views:
  - type: table | cards | list | map
    name: "View Name"
    limit: 10                    # Optional: limit results
    groupBy:                     # Optional: group results
      property: property_name
      direction: ASC | DESC
    filters:                     # View-specific filters (same syntax as global)
      and: []
    order:                       # Properties to display in order
      - file.name
      - property_name
      - formula.formula_name
    summaries:                   # Map properties to summary formulas
      property_name: Average

Filter Syntax

# Single filter
filters: 'status == "done"'

# AND / OR / NOT
filters:
  and:
    - 'status == "done"'
    - 'priority > 3'

# Nested filters
filters:
  or:
    - file.hasTag("tag")
    - and:
        - file.hasTag("book")
        - file.hasLink("Textbook")
    - not:
        - file.hasTag("archived")

Filter Operators

Properties

Three types of properties:

1. Note properties - From frontmatter: author or note.author
2. File properties - File metadata: file.name, file.mtime, etc.
3. Formula properties - Computed values: formula.my_formula

File Properties

The this Keyword

• In main content area: refers to the base file itself
• When embedded: refers to the embedding file
• In sidebar: refers to the active file in main content

Formulas

formulas:
  total: "price * quantity"
  status_icon: 'if(done, "✅", "⏳")'
  formatted_price: 'if(price, price.toFixed(2) + " dollars")'
  created: 'file.ctime.format("YYYY-MM-DD")'
  days_old: '(now() - file.ctime).days'
  days_until_due: 'if(due_date, (date(due_date) - today()).days, "")'

For the complete function catalog (global, string, number, list, date, duration, file, link, object, regex functions), see references/functions.md.

Default Summary Formulas

Complete Example: Task Tracker

filters:
  and:
    - file.hasTag("task")
    - 'file.ext == "md"'

formulas:
  days_until_due: 'if(due, (date(due) - today()).days, "")'
  is_overdue: 'if(due, date(due) < today() && status != "done", false)'
  priority_label: 'if(priority == 1, "🔴 High", if(priority == 2, "🟡 Medium", "🟢 Low"))'

properties:
  status:
    displayName: Status
  formula.days_until_due:
    displayName: "Days Until Due"
  formula.priority_label:
    displayName: Priority

views:
  - type: table
    name: "Active Tasks"
    filters:
      and:
        - 'status != "done"'
    order:
      - file.name
      - status
      - formula.priority_label
      - due
      - formula.days_until_due
    groupBy:
      property: status
      direction: ASC
    summaries:
      formula.days_until_due: Average

  - type: table
    name: "Completed"
    filters:
      and:
        - 'status == "done"'
    order:
      - file.name
      - completed_date

Common Filter Patterns

# By tag
filters:
  and:
    - file.hasTag("project")

# By folder
filters:
  and:
    - file.inFolder("Notes")

# By date range (last 7 days)
filters:
  and:
    - 'file.mtime > now() - "7d"'

# By property value
filters:
  and:
    - 'status == "active"'
    - 'priority >= 3'

Embedding Bases

![[MyBase.base]]
![[MyBase.base#View Name]]

YAML Quoting Rules

• Use single quotes for formulas containing double quotes: 'if(done, "Yes", "No")'
• Use double quotes for simple strings: "My View Name"

When To Use

• Creating or editing .base files for Obsidian vaults
• Building table, cards, list, or map views over vault notes
• Writing filters, formulas, or summaries for Bases
• User mentions Obsidian Bases, database views, or .base file syntax

Boundaries

• Not for editing standard Obsidian Markdown (use obsidian-markdown skill instead)
• Not for Dataview plugin queries; Bases uses its own YAML schema
• Skip when the user needs a community plugin that is not Bases (e.g., Kanban, Calendar)
• Do not generate Base files that reference plugins or properties the vault does not have

Output

• A valid .base YAML file or YAML code block ready to paste into Obsidian
• Includes views, filters, formulas, properties, and summaries as needed
• Uses correct quoting rules (single quotes for expressions containing double quotes)

Verification

• Output is valid YAML that Obsidian Bases can parse without errors
• All referenced properties, formulas, and summary names are internally consistent
• Filter expressions use only documented operators and functions
• Duration arithmetic accesses numeric fields (.days, .hours) before applying .round()

References

• Bases Syntax
• Functions
• Views
• Formulas

Sibling skills

Three Obsidian-format references, distinguished by file type.

• obsidian-markdown — .md notes with Obsidian extensions (wikilinks, callouts, properties). Use for note authoring; this skill is for the database-view layer over those notes.
• obsidian-canvas — .canvas visual canvases. Orthogonal.