Method: PG::Connection#sync_exec

Defined in:

ext/pg_connection.c

#sync_exec(sql) ⇒ PG::Result #sync_exec(sql) {|pg_result| ... } ⇒ Object

This function has the same behavior as #async_exec, but is implemented using the synchronous command processing API of libpq. It’s not recommended to use explicit sync or async variants but #exec instead, unless you have a good reason to do so.

Both #sync_exec and #async_exec release the GVL while waiting for server response, so that concurrent threads will get executed. However #async_exec has two advantages:

1. #async_exec can be aborted by signals (like Ctrl-C), while #exec blocks signal processing until the query is answered.

2. Ruby VM gets notified about IO blocked operations and can pass them through Fiber.scheduler. So only async_* methods are compatible to event based schedulers like the async gem.

Overloads:

• #sync_exec(sql) ⇒ PG::Result

  Returns:

  • (PG::Result)
• #sync_exec(sql) {|pg_result| ... } ⇒ Object

  Yields:

  • (pg_result)

# File 'ext/pg_connection.c', line 1110

static VALUE
pgconn_sync_exec(int argc, VALUE *argv, VALUE self)
{
	t_pg_connection *this = pg_get_connection_safe( self );
	PGresult *result = NULL;
	VALUE rb_pgresult;

	/* If called with no or nil parameters, use PQexec for compatibility */
	if ( argc == 1 || (argc >= 2 && argc <= 4 && NIL_P(argv[1]) )) {
		VALUE query_str = argv[0];

		result = gvl_PQexec(this->pgconn, pg_cstr_enc(query_str, this->enc_idx));
		rb_pgresult = pg_new_result(result, self);
		pg_result_check(rb_pgresult);
		if (rb_block_given_p()) {
			return rb_ensure(rb_yield, rb_pgresult, pg_result_clear, rb_pgresult);
		}
		return rb_pgresult;
	}
	pg_deprecated(0, ("forwarding exec to exec_params is deprecated"));

	/* Otherwise, just call #exec_params instead for backward-compatibility */
	return pgconn_sync_exec_params( argc, argv, self );

}