![]() ![]() ![]() I'm just not as good at macros in Elixir/Ecto to do it (yet). Next, we tell our leftjoin clause what tables to join join the posts table using the userid foreign key, then join the comments table using the postid foreign key. The list of fields is known at compile time. Let’s break it down: First, we create a binding for the user’s data, in this case user (it can be named anything, like u or foo as long as it’s consistent in the query expression). I think technically it is possible to rely on _schema_(:fields) instead of listing all fields explicitly. ![]() greg-rychlewski merged 2 commits into elixir-ecto: master from greg-rychlewski: subqueryatomliteral Apr 17, 2022. Questions = Enum.map_join(fields, ", ", fn _ -> "?" run do The issue seems to be that the planner wasnt ignoring atom literals when collecting for a subquery, causing it to show up in the sql statement. This is what I got so far: defmodule Magic do I also made an attempt to make it more flexible by using Badge._schema_(:fields) and Badge._schema_(:source), but stumbled upon the inability of fragment to accept variable number of arguments. It is very powerful and can be used for all the interaction with databases you need, such as inserting, validating, changing, and querying data. "json_agg((?, ?, ?, ?, ?, ?, ?, ?, ?)::badges)", Ecto is the go-to database toolkit in the Elixir ecosystem, usually used to interact with SQL databases like Postgres and MySQL. The source code of the app I used as a playground is there. I tried this approach myself on a simplified example (without a join). Then the code would look like this: maxrows 500 Purchases > where ( p, p. You could use ectocursorbasedstream library to achieve it. I don't know your schema, so I "made up" 3 columns - I hope you get the idea. As a workaround I recommend streaming the rows without the need of encapsulating that with a transaction, e.g. It cancels the optionality that you want through the left join. If you don’t nest the inner join, then no results will be returned. Preload with Ecto with subquery and using a join from the main query. Ecto Query - Preload one associated object for a number of records. The number of question marks in json_agg should be exactly the same as the number of columns in the profiles table and also the order of columns in the table should correspond to the order of fragment arguments. If you nest the inner join into the left join, and the inner join doesn’t match results, the left join will work, i.e. Elixir & ecto: Subqueries or side loading and normalized json output in view. Join: link in FolderMembership, on: link.profile_id = p.id, Thanks for reporting and the failing test and thanks for the investigation.The solution is not perfect because it requires listing all fields explicitly and also doesn't let you exclude fields from the resulting JSON. The solution is to return a tuple or a map with both post and extra_field keys. select is more generic, so we check when executing. The reason we can do the compile checking for subquery is that subqueries only allow a limited set of expressions. I would like to have all of the items associated with that customer if one of the records has a statusid of 2. ![]() Defp subquery_select ( % does not have the key :extra_field subset from (a in 'table1', where: a.id parameter, where: parentas (:table2).id in a.specialid1, a.specialid2, a.specialid3, select: 1) from (b in 'table2', as: :table2, where: exists (subquery (subset)), select: :firstname, :lastname) That should provide you the query you are looking for. This Ecto query gives me the customers that have an item with a statusid of 2 but it only returns the qualifying item record. ![]()
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