Postgresql is not supported

The Postgresql SQL script should be something like this:

CREATE TABLE "public"."g2_node" (
  "nid" BIGINT DEFAULT 0::bigint NOT NULL, 
  "period" VARCHAR(50), 
  "complement" TEXT, 
  "origin" TEXT, 
  CONSTRAINT "g2_node_pkey" PRIMARY KEY("nid")
) WITH OIDS;

CREATE TABLE "public"."g2_referer" (
  "nid" BIGINT DEFAULT 0::bigint NOT NULL, 
  "referer" VARCHAR(128) DEFAULT ''::character varying NOT NULL, 
  "incoming" BIGINT DEFAULT 0::bigint NOT NULL, 
  CONSTRAINT "g2_referer_pkey" PRIMARY KEY("nid", "referer")
) WITH OIDS;

The SQL queries needs some correction, for example

$sq = "SELECT status, count(distinct n.nid) cnt FROM {node} n ";

should be

$sq = "SELECT status, count(distinct n.nid) AS cnt FROM {node} n ";