Parser improvements

[ironage]

Requested improvements to the query parser are listed below. These features are not required for the query serialisation task but are useful in flushing out the JS query syntax.

Description	Syntax Example
SizeOperator	listproperty[SIZE]
Positional	listproperty[index]
Positional (First)	listproperty[FIRST]
Positional (Last)	listproperty[LAST]
One or more match in collection (membership)	x IN listproperty
Between	x BETWEEN {a, b}
One or more match in collection	ANY listproperty = a
One or more match in collection	SOME listproperty = a
No match in collection	NONE listproperty = a
All entries in collection match	ALL listproperty = a

[ironage]

IN, ANY, SOME, NONE, ALL were added in #2989

We should also add support for SELF to help lookup by primary key:

if (movie.sessions.filtered("SELF == $0", newSession).length == 0) {
    movie.sessions.push(newSession);
}

[RealmBot]

➤ Jørgen Edelbo commented:

[~james.stone] could you give an update on what is actually missing here?

[RealmBot]

➤ James Stone commented:

Updated list of desired features:

DescriptionSyntax ExampleSizeOperatorlistproperty[SIZE]Positionallistproperty[index]Positional (First)listproperty[FIRST]Positional (Last)listproperty[LAST]Betweenx BETWEEN {a, b}primary key lookup on SELFfiltered("SELF == $0", newSession)Long term, we want full support for everything described in the query cheat sheet: https://academy.realm.io/posts/nspredicate-cheatsheet/ ( https://academy.realm.io/posts/nspredicate-cheatsheet/ )

[Deadarius]

Any update on this, specifically IN support?

[ironage]

We also have requests for:

• MATCHES regex operator.
• SELF for primary key lookup and for primitive lists like: var res = myobject.list.filtered(‘SELF = “a” or SELF =“b”’)
• IN where the right operand is a user input list of variables (IN is only currently supported where the right side is a list property in the schema)

[RealmBot]

➤ Ian Ward commented:

[~brian.munkholm] Can we add these to the quarterly backlog please? [~alexander.stigsen] and I ran into these in our IoT research recently

[abhishekmatta999]

Is there any way in Realm to make aggregation(join) b/w two collections

[ironage]

Hi @abhishekmatta999, in Realm you can construct relationships in your schema using links. This should replace the need to use a concept like join from SQL. If you have a specific case where you need help writing a query, please open a separate issue with more detailed information about what you are trying to do and we'd be happy to help. You can also check the docs for some query examples.

[abhishekmatta999]

Hi @abhishekmatta999, in Realm you can construct relationships in your schema using links. This should replace the need to use a concept like join from SQL. If you have a specific case where you need help writing a query, please open a separate issue with more detailed information about what you are trying to do and we'd be happy to help. You can also check the docs for some query examples.

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