Statements

This reference covers the usage of statements in TypeQL.

A TypeQL statement is a building block of a TypeQL pattern. Statements in TypeQL are always end with a semicolon.

Simple statements

A simple statement is the smallest pattern that can be in a TyepQL query.

Most simple statements have two or three parts: <PREDICATE> <SUBJECT>, <SUBJECT> <PREDICATE> or <SUBJECT> <PREDICATE> <OBJECT>, where <PREDICATE> is a TypeQL keyword. However, there can be other more complex statements like let … in statement.

Composite statements

Multiple simple statements with the same subject can be combined into a composite statement. A composite statement starts with a single subject, and multiple comma-separated simple statements with subject omitted.

See an example

Composite statement example

define
  entity user sub profile,
    owns phone,
    owns karma,
    plays parentship:parent,
    plays parentship:child;

The above example combines simple entity, sub, owns, and plays statements to the same result without repeating the subject:

Equal simple statements example

define
  entity user;
  user sub profile;
  user owns phone;
  user owns karma;
  user plays parentship:parent;
  user plays parentship:child;

The comma separation is required before a <PREDICATE> if its <SUBJECT> already has another <PREDICATE> on its right side.

The first two predicates in the example above do not require a comma. However, every simple statement can be separated by commas if preferred.

Definition statements

Definition statements do not contain variables. Most definition statements can also be used as pattern statements.

Type definitions

Entity definitions

entity statement

Used to define a new entity type.

Relation definitions

relation statement

Used to define a new relation type.

relates statement

Used to define a new role for a relation type.

Attribute definitions

attribute statement

Used to define a new attribute type.

value statement

Used to define the value type of an attribute type.

Struct definitions

struct statement

Coming soon

Trait definitions

plays statement

Used to define a new roleplayer for a role.

owns statement

Used to define a new owner of an attribute type.

Subtyping definitions

alias statement

Used to define an alias label for a type.

Function definitions

fun statement

Used to define a function.

Type alias definitions

alias statement

Used to define an alias label for a type.

Pattern statements

Pattern statements are statements that contain variables. Most definition statements can also be used as pattern statements, and will not be repeated in this section (see pages above for their pattern usage).