Easy way to define new attributes to entity after initial schema definition

TypeQL
1

Hi,

In SQL, we can “ALTER TABLE my_table ADD new_column varchar;” to add a new column to an existing table. Can we do the similar in TypeDB? After initially defining the schema, I realised I wanted to define a new attribute to an entity type. I chekced the documentation and there was no obvious solution. There is ‘define’ and ‘undefine’, wondering if there can be an ‘alter’ as well.

Thanks in advance.

2

Hi Alan,

You can use define again to add more attributes to an entity type. Here’s an example:

We initially define a person with a first name.

define 
    first-name sub attribute, value string;
    
    person sub entity, owns first-name;

Following this, we might decide we also want to people to have last names as well.

define
    last-name sub attribute, value string;
    
    person sub entity, owns last-name;

Now, our person entity has both a first-name and a last-name.

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I agree with you that the documentation surrounding the semantics of using define like this could use improvement. I’ve filed an issue with our docs to ensure that this gets addressed.

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