#+TITLE: MU QUERY
#+MAN_CLASS_OPTIONS: :section-id "@SECTION_ID@" :date "@MAN_DATE@"

* NAME

mu-query - a language for finding messages in *mu* databases.

* DESCRIPTION

The mu query language is the language used by *mu find* and *mu4e* to find messages
in *mu*'s Xapian database. The language is quite similar to Xapian's default
query-parser, but is an independent implementation that is customized for the
mu/mu4e use-case.

Here, we give a structured but informal overview of the query language and
provide examples. As a companion to this, we recommend the *mu fields* and *mu
flags* commands to get an up-to-date list of the available fields and flags.

Furthermore, *mu find* provides the ~--analyze~ option, which shows how *mu*
interprets your query; see the *ANALYZING QUERIES* section below.

*NOTE:* if you use queries on the command-line (say, for *mu find*), you need to
quote any characters that would otherwise be interpreted by the shell, such as
*""*, *(* and *)* and whitespace.

* TERMS

The basic building blocks of a query are *terms*; these are just normal words like
`banana' or `hello', or words prefixed with a field-name which makes them apply
to just that field. See *mu info fields* for all the available fields.

Some example queries:
#+begin_example
vacation
subject:capybara
maildir:/inbox
#+end_example

Terms without an explicit field-prefix, (like `vacation' above) are interpreted
like:
#+begin_example
to:vacation or subject:vacation or body:vacation or ...
#+end_example

The language is case-insensitive for terms and attempts to `flatten' diacritics,
so =angtrom= matches =Ångström=.

If terms contain whitespace, they need to be quoted:
#+begin_example
subject:"hi there"
#+end_example
This is a so-called =phrase query=, which means that we match against subjects
that contain the literal phrase "hi there". Phrase queries only work for fields
that are /indexed/, i.e., fields with *index* in the *mu info fields* search column.

Remember that you need to escape those quotes when using this from the
command-line:
#+begin_example
mu find subject:\\"hi there\\"
#+end_example

* LOGICAL OPERATORS

We can combine terms with logical operators -- binary ones: *and*, *or*, *xor* and the
unary *not*, with the conventional rules for precedence and association. The
operators are case-insensitive.

You can also group things with *(* and *)*, so you can write:
#+begin_example
(subject:beethoven or subject:bach) and not body:elvis
#+end_example

If you do not explicitly specify an operator between terms, *and* is implied, so
the queries
#+begin_example
subject:chip subject:dale
#+end_example
#+begin_example
subject:chip AND subject:dale
#+end_example
are equivalent. For readability, we recommend the second version.

Note that a =pure not= - e.g. searching for *not apples* is quite a `heavy' query.

* REGULAR EXPRESSIONS AND WILDCARDS

The language supports matching basic PCRE regular expressions, see *pcre(3)*.

Regular expressions are enclosed in *//*. Some examples:

#+begin_example
subject:/h.llo/		# match hallo, hello, ...
subject:/
#+end_example

Note the difference between `maildir:/foo' and `maildir:/foo/'; the former
matches messages in the `/foo' maildir, while the latter matches all messages in
all maildirs that match `foo', such as `/foo', `/bar/cuux/foo', `/fooishbar'
etc.

Wildcards are another mechanism for matching where a term with a rightmost ***
(and =only= in that position) matches any term that starts with the part before
the ***; they are therefore less powerful than regular expressions, but also much
faster:
#+begin_example
foo*
#+end_example
is equivalent to
#+begin_example
/foo.*/
#+end_example

Regular expressions can be useful, but are relatively slow.

* FIELDS

We already saw a number of search fields, such as *subject:* and *body:*. For the
full table with all details, including single-char shortcuts, try the command:
~mu info fields~.

#+ATTR_MAN: :disable-caption t
#+begin_example
+-----------+----------+----------+-----------------------------+
| flag      | shortcut | category | description                 |
+-----------+----------+----------+-----------------------------+
| draft     | D        | file     | Draft (in progress)         |
+-----------+----------+----------+-----------------------------+
| flagged   | F        | file     | User-flagged                |
+-----------+----------+----------+-----------------------------+
| passed    | P        | file     | Forwarded message           |
+-----------+----------+----------+-----------------------------+
| replied   | R        | file     | Replied-to                  |
+-----------+----------+----------+-----------------------------+
| seen      | S        | file     | Viewed at least once        |
+-----------+----------+----------+-----------------------------+
| trashed   | T        | file     | Marked for deletion         |
+-----------+----------+----------+-----------------------------+
| new       | N        | maildir  | New message                 |
+-----------+----------+----------+-----------------------------+
| signed    | z        | content  | Cryptographically signed    |
+-----------+----------+----------+-----------------------------+
| encrypted | x        | content  | Encrypted                   |
+-----------+----------+----------+-----------------------------+
| attach    | a        | content  | Has at least one attachment |
+-----------+----------+----------+-----------------------------+
| unread    | u        | pseudo   | New or not seen message     |
+-----------+----------+----------+-----------------------------+
| list      | l        | content  | Mailing list message        |
+-----------+----------+----------+-----------------------------+
| personal  | q        | content  | Personal message            |
+-----------+----------+----------+-----------------------------+
| calendar  | c        | content  | Calendar invitation         |
+-----------+----------+----------+-----------------------------+
#+end_example

(*) The language code for the text-body if found. This works only if ~mu~ was
built with CLD2 support.

There are also the special fields *contact:*, which matches all contact-fields
(=from=, =to=, =cc= and =bcc=), and *recip*, which matches all recipient-fields (=to=, =cc=
and =bcc=).

Hence, for instance,
#+begin_example
contact:fnorb@example.com
#+end_example
is equivalent to
#+begin_example
(from:fnorb@example.com or to:fnorb@example.com or
      cc:from:fnorb@example.com or bcc:fnorb@example.com)
#+end_example

* DATE RANGES

The *date:* field takes a date-range, expressed as the lower and upper bound,
separated by *..*. Either lower or upper (but not both) can be omitted to create
an open range.

Dates are expressed in local time and using ISO-8601 format (YYYY-MM-DD
HH:MM:SS); you can leave out the right part and *mu* adds the rest, depending on
whether this is the beginning or end of the range (e.g., as a lower bound,
`2015' would be interpreted as the start of that year; as an upper bound as the
end of the year).

You can use `/' , `.', `-', `:' and `T' to make dates more human-readable.

Some examples:
#+begin_example
date:20170505..20170602
date:2017-05-05..2017-06-02
date:..2017-10-01T12:00
date:2015-06-01..
date:2016..2016
#+end_example

You can also use the special `dates' *now* and *today*:
#+begin_example
date:20170505..now
date:today..
#+end_example

Finally, you can use relative `ago' times which express some time before now and
consist of a number followed by a unit, with units *s* for seconds, *M* for minutes,
*h* for hours, *d* for days, *w* for week, *m* for months and *y* for years. Some
examples:

#+begin_example
date:3m..
date:2017.01.01..5w
#+end_example

* SIZE RANGES

The *size* or *z* field allows you to match =size ranges= -- that is, match messages
that have a byte-size within a certain range. Units (b (for bytes), K (for 1000
bytes) and M (for 1000 * 1000 bytes) are supported). Some examples:

#+begin_example
size:10k..2m
size:10m..
#+end_example

* FLAG FIELD

The *flag/g* field allows you to match message flags. The following fields are
available:
#+begin_example
+-----------+----------+----------+-----------------------------+
| flag      | shortcut | category | description                 |
+-----------+----------+----------+-----------------------------+
| draft     | D        | file     | Draft (in progress)         |
+-----------+----------+----------+-----------------------------+
| flagged   | F        | file     | User-flagged                |
+-----------+----------+----------+-----------------------------+
| passed    | P        | file     | Forwarded message           |
+-----------+----------+----------+-----------------------------+
| replied   | R        | file     | Replied-to                  |
+-----------+----------+----------+-----------------------------+
| seen      | S        | file     | Viewed at least once        |
+-----------+----------+----------+-----------------------------+
| trashed   | T        | file     | Marked for deletion         |
+-----------+----------+----------+-----------------------------+
| new       | N        | maildir  | New message                 |
+-----------+----------+----------+-----------------------------+
| signed    | z        | content  | Cryptographically signed    |
+-----------+----------+----------+-----------------------------+
| encrypted | x        | content  | Encrypted                   |
+-----------+----------+----------+-----------------------------+
| attach    | a        | content  | Has at least one attachment |
+-----------+----------+----------+-----------------------------+
| unread    | u        | pseudo   | New or not seen message     |
+-----------+----------+----------+-----------------------------+
| list      | l        | content  | Mailing list message        |
+-----------+----------+----------+-----------------------------+
| personal  | q        | content  | Personal message            |
+-----------+----------+----------+-----------------------------+
| calendar  | c        | content  | Calendar invitation         |
+-----------+----------+----------+-----------------------------+
#+end_example

Some examples:
#+begin_example
flag:attach
flag:replied
g:x
#+end_example

Encrypted messages may be signed as well, but this is only visible after
decrypting and thus invisible to *mu*.

* PRIORITY FIELD

The message priority field (*prio:*) has three possible values: *low*, *normal* or
*high*. For instance, to match high-priority messages:
#+begin_example
prio:high
#+end_example

* MAILDIR

The Maildir field describes the directory path starting *after* the Maildir root
directory, and before the =/cur/= or =/new/= part. So, for example, if there's a
message with the file name =~/Maildir/lists/running/cur/1234.213:2,=, you could
find it (and all the other messages in that same maildir) with:
#+begin_example
maildir:/lists/running
#+end_example

Note the starting `/'. If you want to match mails in the `root' maildir, you can
do with a single `/':
#+begin_example
maildir:/
#+end_example

If you have maildirs (or any fields) that include spaces, you need to quote
them, ie.
#+begin_example
maildir:"/Sent Items"
#+end_example

And once again, note that when using the command-line, such queries must be
quoted:
#+begin_example
mu find 'maildir:"/Sent Items"'
#+end_example

Also note that you should *not* end the maildir with a ~/~, or it can be
misinterpreted as a regular expression term; see aforementioned.

* MORE EXAMPLES

Here are some simple examples of *mu* queries; you can make many more complicated
queries using various logical operators, parentheses and so on, but in the
author's experience, it's usually faster to find a message with a simple query
just searching for some words.

Find all messages with both `bee' and `bird' (in any field)
#+begin_example
bee AND bird
#+end_example

Find all messages with either Frodo or Sam:
#+begin_example
Frodo OR Sam
#+end_example

Find all messages with the `wombat' as subject, and `capybara' anywhere:
#+begin_example
subject:wombat and capybara
#+end_example

Find all messages in the `Archive' folder from Fred:
#+begin_example
from:fred and maildir:/Archive
#+end_example

Find all unread messages with attachments:
#+begin_example
flag:attach and flag:unread
#+end_example

Find all messages with PDF-attachments:
#+begin_example
mime:application/pdf
#+end_example

Find all messages with attached images:
#+begin_example
mime:image/*
#+end_example

Find all messages written in Dutch or German with the word `hallo':
#+begin_example
hallo and (lang:nl or lang:de)
#+end_example

This is only available if your *mu* has support for this; see *mu info* and check
for "cld2-support*.

* ANALZYING QUERIES

Despite all the excellent documentation, in some cases it can be non-obvious how
~mu~ interprets your query. For that, you can ask ~mu~ to analyze the query -- that
is, show how ~mu~ interprets the query.

This uses the the ~--analyze~ option to *mu find*.
#+begin_example
$ mu find subject:wombat AND date:3m.. size:..2000  --analyze
,* query:
  subject:wombat AND date:3m.. size:..2000
,* parsed query:
  (and (subject "wombat") (date (range "2023-05-30T06:10:09Z" "")) (size (range "" "2000")))
,* Xapian query:
  Query((Swombat AND VALUE_GE 4 n64759341 AND VALUE_LE 17 i7d0))
#+end_example

The ~parsed query~ is usually the most useful one for understanding how *mu*
interprets your query.

#+include: "prefooter.inc" :minlevel 1

* SEE ALSO

*mu-find(1)*, *mu-info(1), *pcre(3)*