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postgres insert using CTE and use the inersted id in next sub query

I insert a user into the database. Then I need the user id generated to insert into a teamMember table. I am using CTE’s, I read they run concurrently, is it possible to return the id of the inserted users to the next statement?

    with INPUT (col) as (
        VALUES ('
            {
               "insert":[
                {"username":"JSmith", "name":"John Smith", "mail":"JSmith@smith.com","jobTitle":"Lead","hasImage":true,"teamId":47}
               ],
               "delete":[
               ],
               "update":[{"username":"JDoe", "name":"Jane Doe","mail":"JDoe@mark.com","jobTitle":"Software Developer","hasImage":false, "uid": 255, "teamId":40}]
            }'::jsonb)
    ), 
    -- Insert new users if username is unique
    do_insert as ( 
      INSERT INTO users (username, name, mail, "jobTitle", "hasImage")
      SELECT i.value ->> 'username',
             i.value ->> 'name', 
             i.value ->> 'mail',
             i.value ->> 'jobTitle',
             (i.value ->> 'hasImage')::boolean
      FROM INPUT
       CROSS JOIN json_array_elements(to_json(col -> 'insert')) i
        WHERE NOT EXISTS (
            SELECT (username) FROM users
            WHERE username = i.value ->> 'username' 
        )
        RETURNING *
    )
    -- Insert row in teamMembers
        INSERT INTO "teamMembers"("teamId", "userId")
      select (i.value ->> 'teamId')::int, t1.id
      from input
       cross join json_array_elements(to_json(col -> 'insert')) i
        left join users t1 ON i.value ->> 'username' = t1.username
left join do_insert on users.username = do_insert.username

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Answer

You don’t need the left join on users since do_insert is the same table but updated. In your select put do_insert.id instead of t1.id and get rid of the users left join and it should work.

    with INPUT (col) as (
        VALUES ('
            {
               "insert":[
                {"username":"JSmith", "name":"John Smith", "mail":"JSmith@smith.com","jobTitle":"Lead","hasImage":true,"teamId":47}
               ],
               "delete":[
               ],
               "update":[{"username":"JDoe", "name":"Jane Doe","mail":"JDoe@mark.com","jobTitle":"Software Developer","hasImage":false, "uid": 255, "teamId":40}]
            }'::jsonb)
    ), 
    -- Insert new users if username is unique
    do_insert as ( 
      INSERT INTO users (username, name, mail, "jobTitle", "hasImage")
      SELECT i.value ->> 'username',
             i.value ->> 'name', 
             i.value ->> 'mail',
             i.value ->> 'jobTitle',
             (i.value ->> 'hasImage')::boolean
      FROM INPUT
       CROSS JOIN json_array_elements(to_json(col -> 'insert')) i
        WHERE NOT EXISTS (
            SELECT (username) FROM users
            WHERE username = i.value ->> 'username' 
        )
        RETURNING *
    )
    -- Insert row in teamMembers
        INSERT INTO "teamMembers"("teamId", "userId")
      select (i.value ->> 'teamId')::int, do_insert.id
      from input
       cross join json_array_elements(to_json(col -> 'insert')) i
      left join do_insert on users.username = do_insert.username
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