Lotus.Storage.Query (Lotus v1.0.0)

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Represents a saved Lotus query.

Queries can be stored, updated, listed, and executed by the host app. Supports {{var}} placeholders in the SQL statement for value substitution only. Variables are bound at runtime using configured variables and are only safe for SQL values (WHERE clauses, ORDER BY values, etc.), never for identifiers like table names, column names, or schema names.

Summary

Functions

Compiles a stored query into an executable Lotus.Query.Statement.

Returns a MapSet of variable names that appear inside [[...]] optional clause blocks in the given SQL statement.

Extracts unique variable names from an SQL statement in order of first occurrence.

Types

t()

@type t() :: %Lotus.Storage.Query{
  __meta__: term(),
  data_source: String.t() | nil,
  description: String.t() | nil,
  id: term(),
  inserted_at: DateTime.t(),
  name: String.t(),
  query_language: String.t() | nil,
  search_path: String.t() | nil,
  statement: String.t(),
  updated_at: DateTime.t(),
  variables: [Lotus.Storage.QueryVariable.t()]
}

Functions

changeset(query, attrs)

compile(q, supplied_vars \\ %{})

@spec compile(t(), map()) :: {:ok, Lotus.Query.Statement.t()} | {:error, String.t()}

Compiles a stored query into an executable Lotus.Query.Statement.

Resolves {{variable}} placeholders, casts the supplied values, and folds them through the source adapter's substitution callbacks. The returned statement carries the adapter-native :body (SQL for Ecto adapters, a DSL / AST / JSON payload for others) and the bound :params.

Returns {:ok, %Lotus.Query.Statement{}} on success, or {:error, reason} when a required variable is missing, a list variable is empty, or a supplied value fails type casting.

Use compile!/2 if you prefer a raising variant.

compile!(q, supplied_vars \\ %{})

@spec compile!(t(), map()) :: Lotus.Query.Statement.t()

Same as compile/2 but raises ArgumentError on error.

extract_optional_variable_names(statement)

@spec extract_optional_variable_names(String.t()) :: MapSet.t()

Returns a MapSet of variable names that appear inside [[...]] optional clause blocks in the given SQL statement.

extract_variables_from_statement(statement)

@spec extract_variables_from_statement(String.t()) :: [String.t()]

Extracts unique variable names from an SQL statement in order of first occurrence.

Variables are identified by the {{variable_name}} syntax.

Examples

iex> Lotus.Storage.Query.extract_variables_from_statement("SELECT * FROM users WHERE id = {{user_id}} AND status = {{status}}")
["user_id", "status"]

iex> Lotus.Storage.Query.extract_variables_from_statement("SELECT * FROM users WHERE id = {{user_id}} OR id = {{user_id}}")
["user_id"]

iex> Lotus.Storage.Query.extract_variables_from_statement("SELECT * FROM users")
[]

new(attrs)

update(query, attrs)