vbmithr / ppx_pgsql

ppx_pgsql

Syntax extension for embedded SQL queries using PG'OCaml.

How it works

Expressions of the form [%sqlf <sql string>] are validated and converted into a function that will execute the query. The generated function will take each named argument (denoted as names starting with the dollar symbol, e.g. $parameter_name) as a keyword argument with the same name, and a database handle as the last argument.

Example:

  let update_account =
    [%sqlf {|
      UPDATE accounts
         SET email = $email, account_type = $account_type
       WHERE account_id = $account_id
   RETURNING account_id, created_at, account_type, email
    |}]

The type of update_account is:

email:string ->
account_type:string ->
account_id:int64 ->
(string, bool) Hashtbl.t Pg_store_helpers.PGOCaml.t ->
(int64 * CalendarLib.Calendar.t * string * string) list
PGOCaml.monad

Named arguments syntax

• $name - normal value
• $@name - list expression value
• $?name - option value (None becomes NULL)
• $@?name - option list expression value

To install

opam pin add ppx_pgsql -k git https://github.com/tizoc/ppx_pgsql.git