# Expressions In addition to the expressions listed in the [Ash expressions guide](https://hexdocs.pm/ash/expressions.html), AshSqlite provides the following expressions # Fragments Fragments allow you to use arbitrary sqlite expressions in your queries. Fragments can often be an escape hatch to allow you to do things that don't have something officially supported with Ash. ### Examples #### Simple expressions ```elixir fragment("? / ?", points, count) ``` #### Calling functions ```elixir fragment("repeat('hello', 4)") ``` #### Using entire queries ```elixir fragment("points > (SELECT SUM(points) FROM games WHERE user_id = ? AND id != ?)", user_id, id) ``` > ### a last resport {: .warning} > > Using entire queries as shown above is a last resort, but can sometimes be the best way to accomplish a given task. #### In calculations ```elixir calculations do calculate :lower_name, :string, expr( fragment("LOWER(?)", name) ) end ``` #### In migrations ```elixir create table(:managers, primary_key: false) do add :id, :uuid, null: false, default: fragment("UUID_GENERATE_V4()"), primary_key: true end ``` ## Like These wrap the sqlite builtin like operator Please be aware, these match _patterns_ not raw text. Use `contains/1` if you want to match text without supporting patterns, i.e `%` and `_` have semantic meaning! For example: ```elixir Ash.Query.filter(User, like(name, "%obo%")) # name contains obo anywhere in the string, case sensitively ```