pk generator progress and sequence test progress

backends/postgres/src/postgres_connection.cpp

@@ -129,6 +129,20 @@ std::string postgres_connection::generate_statement_name(const sql::query_contex
   return name.str();
 }
 
+utils::result<sql::execute_result, utils::error> postgres_connection::execute(const std::string& stmt) const {
+    PGresult *res = PQexec(conn_, stmt.c_str());
+
+    if (const auto status = PQresultStatus(res); status != PGRES_COMMAND_OK && status != PGRES_TUPLES_OK) {
+        return utils::failure(make_error(sql::error_code::FAILURE, res, conn_, "Failed to execute", stmt));
+    }
+
+    const size_t affected_rows = utils::to<size_t>(PQcmdTuples(res));
+
+    PQclear(res);
+
+    return utils::ok(sql::execute_result{affected_rows});
+}
+
 utils::result<std::unique_ptr<sql::statement_impl>, utils::error> postgres_connection::prepare(const sql::query_context &context) {
   auto statement_name = generate_statement_name(context);
 
@@ -143,9 +157,7 @@ utils::result<std::unique_ptr<sql::statement_impl>, utils::error> postgres_conne
 }
 
 utils::result<sql::execute_result, utils::error> postgres_connection::execute(const sql::query_context &context) {
-  if (context.command == sql::sql_command::Insert) {
-    // handle insert command with the primary key generator strategy
-  }
+  return execute(context.sql);
   PGresult *res = PQexec(conn_, context.sql.c_str());
 
   if (const auto status = PQresultStatus(res); status != PGRES_COMMAND_OK && status != PGRES_TUPLES_OK) {
@@ -299,7 +311,17 @@ utils::result<bool, utils::error> postgres_connection::exists(const std::string
 }
 
 utils::result<bool, utils::error> postgres_connection::sequence_exists(const std::string& schema_name, const std::string& sequence_name) {
-  return utils::ok(false);
+    const std::string sql{"SELECT to_regclass('" + schema_name + "." + sequence_name + "')"};
+    PGresult* res = PQexec(conn_, sql.c_str());
+
+    if (PQresultStatus(res) != PGRES_TUPLES_OK) {
+        return utils::failure(make_error(sql::error_code::SEQUENCE_EXISTS_FAILED, res, conn_, "Failed check if sequence exists", sql));
+    }
+
+    const bool exists = PQgetisnull(res, 0, 0) ? false : true;
+    PQclear(res);
+
+    return utils::ok(exists);
 }
 
 std::string postgres_connection::to_escaped_string(const utils::blob_type_t &value) const {