List all items of a given Entity (scan-like)

[zirkelc]

Hi,

all my entities have tenantId as part of the pk, but now I have the use case to list all Tenants. That means I don't have any param I could use for the query. So it's basically a scan operation without any params. Nonetheless, I was wondering if there is any way to make this more performant.

I was thinking I could create a 5th index gsi5pk-gsi5sk-index on the entity name __edb_e__? I assume I would have to create a local attribute that stores an additional copy of __edb_e__ in order to use it as composite index.

Is there another option I'm overseeing here?

[zirkelc]

It was even easier than I thought: #210

[zirkelc]

@tywalch sorry to ping you directly, but I'd like to hear your opinion on this:

Is there any obvious disadvantage when configuring the primary index like this. with an empty pk and the sk making up the full key:

indexes: {
  task: {
    pk: {
      field: "pk",
      composite: [],
    },
    sk: {
      field: "sk",
      composite: ["task", "project", "employee"],
    },
  }
},

// vs.

indexes: {
  task: {
    pk: {
      field: "pk",
      composite: ["task"],
    },
    sk: {
      field: "sk",
      composite: ["project", "employee"],
    },
  }
},

The latter options offers 4 access patterns:

Task.get({ task: "task", project: "project", employee: "employee" }).go();
Task.query.task({ task: "task" }).go();
Task.query.task({ task: "task", project: "project" }).go();
Task.query.task({ task: "task", project: "project", employee: "employee" }).go();

However, the first option offers an additional access pattern to read all Tasks:

Task.get({ task: "task", project: "project", employee: "employee" }).go();
Task.query.task({ task: "task" }).go();
Task.query.task({ task: "task", project: "project" }).go();
Task.query.task({ task: "task", project: "project", employee: "employee" }).go();

Task.query.task({}).go();

Here are the two Playgrounds to test ts:
Without pk

With pk

In combination with scope, the first option looks like better option, right?

[lukemorton]

Useful, thanks for sharing. Worth adding this pattern to the docs I think!