From 54015bfbe98cfd850e1a6c142d8f514a9f48ddd9 Mon Sep 17 00:00:00 2001 From: Marcos Magueta Date: Sat, 7 Mar 2026 20:47:16 -0300 Subject: wip: drl executor --- lib/drl/ast.ml | 25 +++++++++++++++++++++++++ 1 file changed, 25 insertions(+) create mode 100644 lib/drl/ast.ml (limited to 'lib/drl/ast.ml') diff --git a/lib/drl/ast.ml b/lib/drl/ast.ml new file mode 100644 index 0000000..f94965d --- /dev/null +++ b/lib/drl/ast.ml @@ -0,0 +1,25 @@ +open Sexplib.Std + +(** Literal values for Const nodes *) +type value = + | Int of int + | Float of float + | Str of string + | Bool of bool +[@@deriving sexp] + +type direction = Asc | Desc +[@@deriving sexp] + +type query = + | Base of string (** base relation by name *) + | Const of (string * value) list (** constant single-tuple relation *) + | Select of query * query (** σ semijoin: (filter, source) *) + | Join of string list * query * query (** ⋈ natural equijoin on named attrs *) + | Cartesian of query * query (** × Cartesian product *) + | Project of string list * query (** π restrict columns *) + | Rename of (string * string) list * query (** ρ rename (old,new) pairs *) + | Union of query * query (** ∪ — compatible schemas assumed *) + | Diff of query * query (** − *) + | Take of int * query (** τ *) +[@@deriving sexp] -- cgit v1.2.3