Obsidian Bases

Expert knowledge for creating and managing Obsidian Bases - the interactive database feature introduced in Obsidian v1.9.10 that transforms notes into filterable, sortable views using YAML frontmatter properties.

Core Concepts

What is Bases?

• Native core plugin (no community plugins required)
• Creates interactive database views from any set of notes
• Uses .base file extension (plain-text YAML format)
• Only reads YAML frontmatter - does not parse note content
• Faster performance than Dataview with inline editing support

Key Distinction from Dataview:

• Bases: User-friendly, visual, inline editable, YAML frontmatter only
• Dataview: More powerful queries, inline properties, content parsing

File Structure

# example.base
filters:
  # Global filters (apply to all views)
  and:
    - 'status != "done"'
    - taggedWith(file.file, "project")

formulas:
  # Computed properties
  days_left: '(dueDate - today()).days()'
  status_icon: 'if(done, "✅", "⬜")'

views:
  - type: table
    name: "Active Tasks"
    filters:
      'dueDate > now()'      # View-specific filter
    properties:
      - name: title
        displayName: "Task"
      - name: status
      - name: dueDate
    sort:
      - property: dueDate
        direction: asc

  - type: card
    name: "Visual View"
    properties:
      - name: cover
      - name: title

Property Access Patterns

Note Properties (Frontmatter)

# Shorthand access
price
status
tags

# Explicit prefix
note.price
note.status

# Bracket notation (for spaces)
note["property name"]

File Properties (Implicit)

file.path      # Full file path
file.name      # File name only
file.folder    # Parent folder
file.size      # File size in bytes
file.ctime     # Creation time
file.mtime     # Modification time
file.ext       # Extension
file.file      # File object (for filter functions)
file.links     # Outgoing links
file.inlinks   # Incoming backlinks

Formula Properties

formula.my_formula
formula["formula name"]

Filter Syntax

Basic Operators

# Comparison (must have spaces around operators)
price > 10
status == "done"
age >= 18

# Logical operators
and:
  - condition1
  - condition2

or:
  - condition1
  - condition2

not:
  - condition

Filter Functions

# Tag filtering
taggedWith(file.file, "project")
taggedWith(file.file, "project/web")     # Nested tags

# Link filtering
linksTo(file.file, "Note Name")
file.hasLink(this.file)                  # Backlinks to current note

# Folder filtering
inFolder(file.file, "Projects")
inFolder(file.file, "Projects/Web")      # Nested folders

# Date filtering
file.mtime > now() - "1 week"            # Modified recently
dueDate < today()                        # Overdue
createdDate >= "2025-01-01"              # This year

# Regex matching
/\d{4}-\d{2}-\d{2}/.matches(file.name)   # Daily note format

The this Variable

Context-aware reference to the active note:

# In sidebar: references active note in main pane
file.hasLink(this.file)                  # Find backlinks

# In embedded base: references containing note
file.folder == this.file.folder          # Same folder

# Exclude current note
file.path != this.file.path

Formula Syntax

Basic Formulas

formulas:
  # Arithmetic
  total: "price * quantity"
  discounted: "total * 0.9"

  # String manipulation
  full_name: 'firstName + " " + lastName'

  # Conditional logic
  status_emoji: 'if(status == "done", "✅", if(status == "in-progress", "🔄", "⬜"))'

  # Date calculations
  days_until: '(dueDate - today()).days()'
  overdue: 'dueDate < today()'

  # Link analysis
  backlink_count: 'file.inlinks.length'
  has_backlinks: 'file.inlinks.length > 0'

Built-in Functions

Global:

• today() - Current date
• now() - Current date and time
• link(target, displayText?) - Create link
• image(url) - Create image object
• list(value) - Ensure value is a list
• if(condition, trueResult, falseResult?) - Conditional

String methods:

• .toUpperCase(), .toLowerCase()
• .trim(), .split(separator)
• .startsWith(prefix), .endsWith(suffix)
• .replace(search, replacement)

Number methods:

• .toFixed(decimals) - Format decimal places
• .round(), .floor(), .ceil()

Date methods:

• .date() - Convert to date
• .startOf(unit), .endOf(unit)
• .format(pattern)
• .days(), .months(), .years() - Duration extraction

List methods:

• .length - Count elements
• [index] - Access element (0-based)
• .filter(condition) - Filter elements
• .map(transformation) - Transform elements
• .join(separator) - Concatenate to string

Duration Units

now() + "1 week"
now() - "30 days"
file.mtime > now() - "1 month"

# Available units
y, year, years
M, month, months
w, week, weeks
d, day, days
h, hour, hours
m, minute, minutes
s, second, seconds

View Types

Table View

views:
  - type: table
    name: "Tasks"
    properties:
      - name: title
        displayName: "Task Name"    # Column header
        width: 200                   # Optional width
      - name: status
      - name: dueDate
    sort:
      - property: dueDate
        direction: asc              # or desc

Card View

views:
  - type: card
    name: "Projects"
    properties:
      - name: cover              # Cover image
      - name: title
      - name: status

Common Patterns

Task Management

filters:
  taggedWith(file.file, "task")

formulas:
  overdue: 'dueDate < today()'
  priority_icon: 'if(priority == "high", "🔴", if(priority == "medium", "🟡", "🟢"))'

views:
  - type: table
    name: "Active"
    filters:
      'status != "done"'
    sort:
      - property: dueDate
        direction: asc

Enhanced Backlinks

# Drag to sidebar for context-aware backlinks
filters:
  file.hasLink(this.file)

views:
  - type: table
    name: "Backlinks"
    properties:
      - name: file.name
        displayName: "Note"
      - name: file.mtime
        displayName: "Modified"

Book/Media Library

filters:
  taggedWith(file.file, "book")

formulas:
  year_read: 'dateFinished.date().year()'

views:
  - type: card
    name: "Library"
    properties:
      - name: cover
      - name: title
      - name: author

  - type: table
    name: "Reading List"
    filters:
      'status == "to-read"'

Weekly Review

filters:
  file.mtime > now() - "1 week"

formulas:
  days_ago: '(today() - file.mtime.date()).days()'

views:
  - type: table
    name: "Recent Activity"
    sort:
      - property: file.mtime
        direction: desc

Embedding Bases

![[MyBase.base]]                # Embed entire base
![[MyBase.base#ViewName]]       # Embed specific view

Best Practices

Filter Organization:

• Use global filters for the broadest scope (lowest common denominator)
• Refine with view-level filters for specific subsets
• Global + view filters combine with AND

Formula Reusability:

• Create formula properties for repeated logic
• Reference as formula.name in views
• No circular references allowed

Robust List Handling:

# Always wrap in list() for mixed single/array values
list(tags).length
list(tags).filter(value.startsWith("project"))

Date Validation:

valid_date: 'if(dueDate, dueDate, "No date")'

Common Gotchas

1. Arithmetic operator spacing:

# ✅ Correct
price * 2

# ❌ Wrong (parser error)
price*2

2. Quote nesting in YAML:

# ✅ Correct - single outer, double inner
formulas:
  message: 'Hello "world"'

# ❌ Wrong
formulas:
  message: "Hello "world""

3. Link properties in frontmatter:

# ✅ Correct - must quote
related: "[[Other Note]]"

# ❌ Wrong
related: [[Other Note]]

4. File extension required:

<!-- ✅ Correct -->
![[MyBase.base]]

<!-- ❌ Wrong (looks for .md) -->
![[MyBase]]

5. Global vs view filter scope:

• Cannot override global filter at view level
• Make global permissive, refine in views

Current Limitations

• View types: Only table and card (no board, calendar, gallery yet)
• Images: Display as text, not rendered in cards
• Inline properties: Only YAML frontmatter (no Dataview inline fields)
• Content parsing: Cannot query note body text
• Note creation: Cannot create new notes from base
• Grouping: No native group-by (use separate views instead)
• Aggregations: No built-in sum/average/count

Property Types

Type	Example
Text	"Project Alpha"
List	["tag1", "tag2"]
Number	42, 3.14
Checkbox	true, false
Date	2025-11-26
Date & Time	2025-11-26T14:30:00

Note: Property types are vault-wide. If priority is Number in one note, it must be Number everywhere.

Resources

• Official Docs: https://help.obsidian.md/bases
• Syntax Reference: https://help.obsidian.md/bases/syntax
• Functions: https://help.obsidian.md/bases/functions
• Roadmap: https://help.obsidian.md/bases/roadmap