Dataview Plugin

· Dataview docs · Obsidian Example Vault for Dataview Queries · #note/sink ·

TOC

• Inline
• Implicit fields
• Tasks and tasks list metadata
• DQL
  • Query format
• Expressions
  • Functions
    • Numeric
    • Strings
    • Utility
    • Java

Inline

For those wanting a more natural-looking annotation, Dataview supports "inline" fields via a Key:: Value syntax that you can use everywhere in your file. This allows you to write your queryable data right where you need it - for example in the middle of a sentence.

If your inline field has an own line, without any content beforehand, you can write it like this:

# Markdown Page  Basic Field:: Some random Value **Bold Field**:: Nice!

All content after the :: is the value of the field until the next line break.

Mind the ::
You need to use a double colon :: between key and value when using inline fields, contrary to YAML Frontmatter fields where one colon is enough.

If you want to embed metadata inside sentences, or multiple fields on the same line, you can use the bracket syntax and wrap your field in square brackets:

I would rate this a [rating:: 9]! It was [mood:: acceptable].

Fields on list items and tasks

When you want to annotate a list item, e.g. a task, with metadata, you always need to use the bracket syntax (because the field is not the only information in this line)

- [ ] Send an mail to David about the deadline [due:: 2022-04-05].

Bracketed inline fields are the only way to explicitly add fields to specific list items, YAML frontmatter always applies to the whole page (but is also available in context of list items.)

Implicit fields

Tasks and tasks list metadata

Just like pages, you can also add fields on list item and task level to bind it to a specific task as context. For this you need to use the inline field syntax:

- [ ] Hello, this is some [metadata:: value]!
- [X] I finished this on [completion:: 2021-08-15].

For supporting "common use cases", Dataview understands a few shorthands for some fields you may want to annotate task with:

There are two specifics to these emoji-shorthands. First, they omit the inline field syntax (no [🗓️:: YYYY-MM-DD] needed) and secondly, they map to a textual field name data-wise:

his means if you want to query for all tasks that are completed 2021-08-22, you'll write:

TASK
WHERE completion = date("2021-08-22")

As with pages, Dataview adds a number of implicit fields to each task or list item:

Inheritance of Fields
Tasks inherit all fields from their parent page - so if you have a rating field in your page, you can also access it on your task in a TASK Query.

For TASK queries your tasks are the top level information and can be used without any prefix:

TASK
WHERE !fullyCompleted

LIST
WHERE any(file.tasks, (t) => !t.fullyCompleted)

DQL

Query format

• QUERY: Choosing an output format of your output (the Query Type)

  • TABLE
  • LIST
  • TASK
  • CALENDAR

• FROM: Fetch pages from a certain source, i.e. a tag, folder or link

  • FROM "Books" - all links to the note
  • FROM outgoing([[Dashboard]]) - all outgoing links
  • FROM [[]] - links to current note
  • FROM status/open OR status/wip
  • FROM (#assignment AND "30 School") OR ("30 School/32 Homeworks" AND outgoing([[School Dashboard Current To Dos]]))
  • FROM -#tag will exclude files which have the given tag
  • FROM #tag and -"folder" will only include files tagged #tag which are NOT in "folder"
  • FROM #tag and ("folder" or #other-tag)

• WHERE: Filtering pages/data by simple operations on fields, like comparison, existence checks, and so on

  • WHERE !completed AND file.ctime <= date(today) - dur(1 month)
  • WHERE contains(L.author, "Surname")
  • WHERE typeof(contacts) = "array" AND contains(contacts, [[Mr. L]])
  • WHERE contains(file.name, "WIP")
  • WHERE string(file.day.year) = split(this.file.name, "-W")[0]
  • WHERE file.day.year = 2022

• FLATTEN: Transforming fields for displaying, i.e. with calculations or splitting up multi-value fields

  • FLATTEN field
  • FLATTEN (computed_field) AS name

• SORT: Sorting results based on fields

  • SORT field1 [ASCENDING/DESCENDING/ASC/DESC], ..., fieldN [ASC/DESC]

• GROUP BY: Grouping results based on fields

  • GROUP BY field
  • GROUP BY (computed_field) AS name

• LIMIT: Limiting your result count

  • LIMIT 5

The Query Type is the only mandatory command in a query. Everything else is optional.

Expressions

Dataview query language expressions are anything that yields a value:

• all fields
• all literals
• and computed values, like field - 9 of function calls.

# Literals
1                   (number)
true/false          (boolean)
"text"              (text)
date(2021-04-18)    (date)
dur(1 day)          (duration)
[[Link]]            (link)
[1, 2, 3]           (list)
{ a: 1, b: 2 }      (object)

#Lambdas (functions)
(x1, x2) => ... (lambda)

# References
field               (directly refer to a field)
simple-field        (refer to fields with spaces/punctuation in them like "Simple Field!")
a.b                 (if a is an object, retrieve field named 'b')
a[expr]             (if a is an object or array, retrieve field with name specified by expression 'expr')
f(a, b, ...)        (call a function called `f` on arguments a, b, ...)

# Arithmetic
a + b               (addition)
a - b               (subtraction)
a * b               (multiplication)
a / b               (division)
a % b               (modulo / remainder of division)

# Comparison
a > b               (check if a is greater than b)
a < b               (check if a is less than b)
a = b               (check if a equals b)
a != b              (check if a does not equal b)
a <= b              (check if a is less than or equal to b)
a >= b              (check if a is greater than or equal to b)

# Strings

a + b               (string concatenation)
a * num             (repeat string <num> times)

# Special Operations
[[Link]].value      (fetch `value` from page `Link`)

Functions

# Functions on lists
lower("YES") = "yes"
lower(["YES", "NO"]) = ["yes", "no"]

replace("yes", "e", "a") = "yas"
replace(["yes", "ree"], "e", "a") = ["yas", "raa"]

# Constructors
object() => empty object
object("a", 6) => object which maps "a" to 6
object("a", 4, "c", "yes") => object which maps a to 4, and c to "yes"

date("2020-04-18") = <date object representing April 18th, 2020>
date([[2021-04-16]]) = <date object for the given page, refering to file.day>

dur(8 minutes) = <8 minutes>

number("18 years") = 18
number(34) = 34
number("hmm") = null

link("Hello") => link to page named 'Hello'
link("Hello", "Goodbye") => link to page named 'Hello', displays as 'Goodbye'

embed(link("Hello.png")) => embedded link to the "Hello.png" image, which will render as an actual image.
elink("www.google.com", "Google") => link element to google.com, displays as "Google"

Numeric

round(number, [digits])
min(a, b, ..)                          or array, or strings by length
max(a, b, ...)                         or array, or strings by length
sum(array)                             sum(nonnull([null, 1, 8])) = 9
product(array)
average(array)
minby(array, function)                 minby([1, 2, 3], (k) => 0 - k) => 3
maxby(array, function)                 maxby(this.file.tasks, (k) => k.due) => (latest due)

contains(object|list|string, value)    contains("Hello", "Lo") = false
icontains(object|list|string, value)   icontains("Hello", "Lo") = true
econtains(object|list|string, value)   econtains("Hello", "lo") = true, econtains(["this","is","example"], "is") = true
contains(file, "ctime") = true         For objects, checks if the object has a key with the given name  
containsword(list|string, value)       For strings, it checks if the word is present in the given string
                                       For lists, it returns a list of booleans indicating
                                           if the word's exact case insensitive match was found

extract(object, key1, key2, ...)       Pulls multiple fields out of an object, creating a new object with just those fields

sort(list)
reverse(list)

length(object|array)

nonnull(array)              Return a new array with all null values removed
all(array)                  Returns true only if ALL values in the array are truthy
                                all([1, 2, 3]) = true
                                all(["apple", "pie", 3], (x) => typeof(x) = "string") = false
any(array)                  Returns true if ANY of the values in the array are truthy    
none(array)                 Returns true if NONE of the values in the array are truthy
                                none(["Apple", "Pi", "Banana"], (x) => startswith(x, "A")) = false
join(array, [delimiter])    join(list(1, 2, 3), " ") = "1 2 3"                    
filter(array, predicate)    Filters elements in an array according to the predicate, returning a new list
                                filter([1, 2, 3], (x) => x >= 2) = [2, 3]
                                filter(["yes", "no", "yas"], (x) => startswith(x, "y")) = ["yes", "yas"]
map(array, func)            Applies the function to each element in the array, returning a list
                                map([1, 2, 3], (x) => x + 2) = [3, 4, 5]
                                map(["yes", "no"], (x) => x + "?") = ["yes?", "no?"]

Strings

regextest(pattern, string)                  Checks if the given regex pattern can be found (JavaScript regex engine)
                                                regextest("\w+", "hello") = true
                                                regextest("what", "what's up dog?") = true
regexreplace(string, pattern, replacement)  regexreplace("yes", "[ys]", "a") = "aea"
                                                regexreplace("Suite 1000", "\d+", "-") = "Suite -"

lower(string)
upper(string)

split(string, delimiter, [split limit])
startswith(string, prefix)                  startswith("path/to/something", "path/") = true
endswith(string, suffix)                    endswith("path/to/something", "something") = true

padleft(string, length, [padding symbol])
padright(string, length, [padding symbol])

substring(string, start, [end])
truncate(string, length, [suffix])

Utility

default(field, value)               If `field` is null, return `value`. Vectorized in both arguments
                                        default(list(1, 2, null), 3) = list(1, 2, 3)
ldefault(field, value)              Same for lists
                                        ldefault(list(1, 2, null), 3) = list(1, 2, null)
choice(bool, left, right)           If the first is truthy, returns left; otherwise - right
                                        choice(x > 4, y, z) = y (if x > 4, else z)

striptime(date)                     Strip the time component of a date to year, month, and day
dateformat(date|datetime, string)   Format a Dataview date 
                                        dateformat(file.ctime,"yyyy-MM-dd") = "2022-01-05"
                                        dateformat(file.ctime,"HH:mm:ss") = "12:18:04"
                                        dateformat(file.mtime,"ffff") = "Wednesday, August 6, 2014 ..."
localtime(date)

meta(link)                Get an object containing metadata of a link
    meta(link).display        meta(Displayed text).display = "Displayed text"
    meta(link).embed          True or false depending on whether the link is an embed
    meta(link).path           Get the path portion of a link
		                          meta([[My Project#Next Actions]]).path = "My Project"
    meta(link).subpath        meta([[My Project#Next Actions]]).subpath = "Next Actions"
                                  meta([[My Project]]).subpath = null
    meta(link).type           Has the value "file", "header", or "block"

Java

More funtions in java

Links