![(please configure the [header_logo] section in trac.ini)](/chrome/site/your_project_logo.png){kind=logo}
Identity-related functions
An aspect's identity and a field's label
| Function | HTSQL | SQL | Javascript | Python |
| Generate the identity part of the aspect locator | a.id() | -- | -- | -- |
| Generate the tag part of the aspect locator | a.tag() | -- | -- | -- |
| Generate the full aspect locator | a.idtag() | -- | -- | -- |
| Escape a value for a locator | v.label() | -- | -- | -- |
Signatures:
- Tuple . htsql:id() -> String
- Tuple . htsql:tag() -> String
- Tuple . htsql:idtag() -> String
- Any . htsql:label() -> String
An aspect locator has the form [id;tag]. The function 'id()' produces the id part of the locator, the function tag() produces the tag part of the locator, and the function idtag() produces id;tag. Note that not all aspects have tags, for those which don't, id() and idtag() produce the same value while tag() produces NULL.
The method htsql:label() is defined for the following domains: Boolean, String, Number, Binary, BitString, Date, Time, DateTime, TimeDelta.
The sieve operator
| Function | HTSQL | SQL | Javascript | Python |
| Sieve a reference | base?filter | -- | -- | -- |
Signatures:
- htsql:operator:"?"(Tuple base, Boolean filter) -> Tuple
The sieve operator applies a filter to an aspect binding and returns the sieved aspect binding.
