title: Search operator
role: manual
tags: #manual #search #zettelstore
syntax: zmk
back: 00001006032000 00001006033000 00001007700000 00001007701000 00001007702000
backward: 00001006032000 00001006033000 00001007700000 00001007701000 00001007702000 00001007706000
box-number: 1
copyright: (c) 2020-present by Detlef Stern <ds@zettelstore.de>
created: 20220805150154
forward: 00001006030000 00001007706000
lang: en
license: EUPL-1.2-or-later
modified: 20230612180539
published: 20230612180539
visibility: public

A search operator specifies how the comparison of a search value and a zettel should be executed.
Every comparison is done case-insensitive, treating all uppercase letters the same as lowercase letters.

The following are allowed search operator characters:
* The exclamation mark character (""''!''"", U+0021) negates the meaning.
* The equal sign character (""''=''"", U+003D) compares on equal content (""equals operator"").
* The tilde character (""''~''"", U+007E) compares on matching (""match operator"").
* The left square bracket character (""''[''"", U+005B) matches if there is some prefix (""prefix operator"").
* The right square bracket character (""'']''"", U+005D) compares a suffix relationship (""suffix operator"").
* The colon character (""'':''"", U+003A) compares depending on the on the actual [[key type|00001006030000]] (""has operator"").
  In most cases, it acts as a equals operator, but for some type it acts as the match operator.
* The less-than sign character (""''<''"", U+003C) matches if the search value is somehow less then the metadata value (""less operator"").
* The greater-than sign character (""''>''"", U+003E) matches if the search value is somehow greater then the metadata value (""greater operator"").
* The question mark (""''?''"", U+003F) checks for an existing metadata key (""exist operator"").
  In this case no [[search value|00001007706000]] must be given.
Since the exclamation mark character can be combined with the other, there are 18 possible combinations:
# ""''!''"": is an abbreviation of the ""''!~''"" operator.
# ""''~''"": is successful if the search value matched the value to be compared.
# ""''!~''"": is successful if the search value does not match the value to be compared.
# ""''=''"": is successful if the search value is equal to one word of the value to be compared.
# ""''!=''"": is successful if the search value is not equal to any word of the value to be compared.
# ""''[''"": is successful if the search value is a prefix of the value to be compared.
# ""''![''"": is successful if the search value is not a prefix of the value to be compared.
# ""'']''"": is successful if the search value is a suffix of the value to be compared.
# ""''!]''"": is successful if the search value is not a suffix of the value to be compared.
# ""'':''"": is successful if the search value is has/match one word of the value to be compared.
# ""''!:''"": is successful if the search value is not match/has to any word of the value to be compared.
# ""''<''"": is successful if the search value is less than the value to be compared.
# ""''!<''"": is successful if the search value is not less than, e.g. greater or equal than the value to be compared.
# ""''>''"": is successful if the search value is greater than the value to be compared.
# ""''!>''"": is successful if the search value is not greater than, e.g. less or equal than the value to be compared.
# ""''?''"": is successful if the metadata contains the given key.
# ""''!?''"": is successful if the metadata does not contain the given key.
# ""''''"": a missing search operator can only occur for a full-text search.
  It is equal to the ""''~''"" operator.