Xata•5mo ago

Reverse links typescript

Hi there. I'm wondering if it's possible to read a ShoppingCart by it's id and also get all it's ShoppingCartLineItems in one query. I'm trying to avoid making multiple queries to the database. I've had a look at https://xata.io/blog/navigating-many-to-one and https://xata.io/docs/concepts/data-model#links-and-relationships but I'm still not sure how to do this. Schema:

{
  "tables": [
    {
      "name": "ShoppingCarts",
      "columns": [
        {
          "name": "customerId",
          "type": "string"
        }
      ],
      "revLinks": [
        {
          "column": "shoppingCart",
          "table": "Users"
        },
        {
          "column": "shoppingCart",
          "table": "ShoppingCartLineItems"
        }
      ]
    },
    {
      "name": "ShoppingCartLineItems",
      "columns": [
        {
          "name": "shoppingCart",
          "type": "link",
          "link": {
            "table": "ShoppingCarts"
          }
        },
        {
          "name": "productId",
          "type": "string"
        },
        {
          "name": "quantity",
          "type": "int"
        },
        {
          "name": "type",
          "type": "string",
          "defaultValue": "product"
        }
      ]
    }
  ]
}

{
  "tables": [
    {
      "name": "ShoppingCarts",
      "columns": [
        {
          "name": "customerId",
          "type": "string"
        }
      ],
      "revLinks": [
        {
          "column": "shoppingCart",
          "table": "Users"
        },
        {
          "column": "shoppingCart",
          "table": "ShoppingCartLineItems"
        }
      ]
    },
    {
      "name": "ShoppingCartLineItems",
      "columns": [
        {
          "name": "shoppingCart",
          "type": "link",
          "link": {
            "table": "ShoppingCarts"
          }
        },
        {
          "name": "productId",
          "type": "string"
        },
        {
          "name": "quantity",
          "type": "int"
        },
        {
          "name": "type",
          "type": "string",
          "defaultValue": "product"
        }
      ]
    }
  ]
}

What seems to work is:

const record = await xata.db.ShoppingCarts.select([{
    name: "<-ShoppingCartLineItems.shoppingCart",
    columns: ["productId", "quantity", "type"],
    as: "lineItems"
}]).filter({ id: "rec_cno400v3e8os6tplq4jg"}).getFirstOrThrow()

const record = await xata.db.ShoppingCarts.select([{
    name: "<-ShoppingCartLineItems.shoppingCart",
    columns: ["productId", "quantity", "type"],
    as: "lineItems"
}]).filter({ id: "rec_cno400v3e8os6tplq4jg"}).getFirstOrThrow()

However, record doesn't have a lineItems prop. 🤔

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5 Replies

kostas•5mo ago

Right, that's because the response record type does not include the lineItems field which is introduced ad-hoc at query time. Try referencing it as record?.lineItems

maxfiOP•5mo ago

So is record.lineItems not strongly typed?

kostas•5mo ago

Yes, it seems the return type does not include aliases. I added a bug report to the client repo: https://github.com/xataio/client-ts/issues/1524

GitHub

Reverse link Aliases are not typed · Issue #1524 · xataio/client-ts

Reported on client version: 0.29.5 When aliasing a reverse link result with as, the alias is not typed in the returned object. const record = await xata.db.ShoppingCarts.select([{ name: "<-...

maxfiOP•5mo ago

Thanks @kostas. 🙏 Doesn't seem to work without the as as well. Is this expected?

kostas•5mo ago

It is the same issue, reverse link results are not typed. I extended the description of the issue for more clarity. Thanks for pointing it out

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Reverse links typescript