title: Supported Key Types
role: manual
tags: #manual #meta #reference #zettel #zettelstore
syntax: zmk

All [[supported metadata keys|00001006020000]] conform to a type.

User-defined metadata keys conform also to a type, based on the suffix of the key.

|=Suffix|Type
| ''-date'' | [[Timestamp|00001006034500]]
| ''-number'' | [[Number|00001006033000]]
| ''-role'' | [[Word|00001006035500]]
| ''-time'' | [[Timestamp|00001006034500]]
| ''-title'' | [[Zettelmarkup|00001006036500]]
| ''-url'' | [[URL|00001006035000]]
| ''-zettel''  | [[Identifier|00001006032000]]
| ''-zid''  | [[Identifier|00001006032000]]
| ''-zids''  | [[IdentifierSet|00001006032500]]
| any other suffix | [[EString|00001006031500]]

The name of the metadata key is bound to the key type

Every key type has an associated validation rule to check values of the given type.
There is also a rule how values are matched, e.g. against a [[search value|00001007706000]] when selecting some zettel.
And there is a rule how values compare for sorting.

* [[Credential|00001006031000]]
* [[EString|00001006031500]]
* [[Identifier|00001006032000]]
* [[IdentifierSet|00001006032500]]
* [[Number|00001006033000]]
* [[String|00001006033500]]
* [[TagSet|00001006034000]]
* [[Timestamp|00001006034500]]
* [[URL|00001006035000]]
* [[Word|00001006035500]]
* [[Zettelmarkup|00001006036500]]