However, execute() returns :ok if successful, so I'm not sure how executing that SELECT statement is helpful. Using Ecto.Query Id like to be able to run a query and prepend a comment like this in Postges: / my comment / SELECT a.col FROM table a Ive tried 'where: fragment', but its not working well, and it makes for messy SQL. How about: execute("SELECT MAX(id) from t2.tenants") Does your database really require you to quote the table name in a SELECT? | | Please help me how to execute select query? execute("(SELECT MAX(id) from \"t2.tenants\")")ġ) Does your database really require parentheses around a SELECT statement? | |Ģ) In your successful INSERT statement, you didn't have to quote the table name. Here's what query looks like: "INSERT INTO t2.tenants Do you enjoy escaping nested quote marks? If not, use ~s|.| or ~s" If you would like to read more articles about Elixir, be sure to follow us on Twitter or Dev.Don't type strings with nested quotes. If Thinking in Ecto was not enough and you would like to see another conference talk by Darin Wilson, this one is a bit more in-depth. For creating/managing views you’ll need to resort to and raw sql though. Just use the names of views you have and you’re good to go. It’s curated by Dashbit, the company working on Elixir. Ecto does not care if you query a table or a view. A cookbook with recipes on how to achieve common Ecto tasks. Elixir School’s Ecto section contains a lot of useful info and code examples on changesets and queries. Remember, the operator (called the pin operator) means we want to keep username the same. the authors of Programming Phoenix state (in chapter 7) that. from u in User, where: u.username username. However, with regard to an Ecto query like. It’s well written and should be able to answer most of your questions. In Elixir, the pin operator is used to prevent variable rebinding. This is a rather large YouTube playlist of 13 videos that goes through some of the basics of Ecto. I’m a fan of the content Alchemist Camp is putting out, and this is no different. Ecto basics playlist from Alchemist Camp.If you are one of those people that can read a book, it can be useful to pick it up. Not much to say – it is the premier Ecto book. It covers what is special about Ecto, and why it is the way it is. If you check out just one resource from this list, watch this talk. Here is a load of awesome beginner- and intermediate-level materials that you can check out to learn more about the toolkit. Each of the items I talked about are covered better in different places I only tried to bring all the knowledge in one place for your convenience. I’ve given a quick introduction, but there’s a lot still to explore out there. If you would like to read more about validations and constraints, this article is very nice. In a previous post I detailed how if youre using one of these Ecto database adapters. There are a lot of ready-made validations present, but you can also write your own custom validation functions and call them with validate_change. Iex(18)> changeset = _required(changeset, ) Now, we can play around with the database.įirst off, some alias preparations: iex(1)> alias Blog.Repo Schema-less queries, pure SQL instead of Ecto.Query, just using changesets for data validation – you want it, you can do it. While Ecto is frequently called a framework, it consists of a few modules, most of which you can use or not use, depending on your preferences. But you can technically use it to connect to whichever data source your heart prefers like MongoDB or ETS, among other things. For example, by default, Ecto is made to connect to SQL databases like MySQL & PostgreSQL. While it can cause some headaches in the start, it prevents you from making mistakes that you will forever remember when your project goes viral on Product Hunt.Ĭonfigurable. For example, if you don’t preload associated items, the framework will not fetch them for you. Ecto is explicit about what is happening: there is not so much behind-the-scenes magic as in other libraries. Generally, Ecto offers the same benefits as other things in the Elixir ecosystem: we focus on modularity and explicitness and of course it has macros.Įxplicit. If you are using Phoenix and Elixir, the chance is you will use Ecto. Most likely, the choice of using Ecto will come as a consequence of other choices that you’ve made.
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