Indexes

This section describes the SDL declarations pertaining to indexes.

Example

Declare an index for a “User” based on the “name” property:

type User {
    required property name -> str;
    property address -> str;
    multi link friends -> User;
    # define an index for User based on name
    index on (.name) {
        annotation title := 'User name index';
    }
}

Syntax

Define a new index corresponding to the more explicit DDL commands.

index on ( index-expr )
[ except ( except-expr ) ]
[ "{" annotation-declarations "}" ] ;

Description

This declaration defines a new index with the following options:

on ( index-expr )

The specific expression for which the index is made. Note also that <index-expr> itself has to be parenthesized.

except ( exception-expr )

• An optional expression defining a condition to create exceptions

  to the index. If <exception-expr> evaluates to true, the object is omitted from the index. If it evaluates to false or {}, it appears in the index.

The valid SDL sub-declarations are listed below:

annotation-declarations

Set index annotation to a given value.

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