refactoring query builder

src/db/dml.rs

@@ -1,16 +1,15 @@
 use deadpool_postgres::Client;
 use tokio_pg_mapper::FromTokioPostgresRow;
-use tokio_postgres::{row, Row};
+use tokio_postgres::{Row, Statement};
 
 use crate::{db::models::Ping, settings::errors::MyError};
 
 // retrieve ping records list
 pub async fn get_ping_records(client: &Client) -> Result<Vec<Ping>, MyError> {
-    let _stmt = include_str!("./sql/ping/get_records.sql");
-    let _stmt = _stmt.replace("$table_fields", &Ping::sql_table_fields());
-    let stmt = client.prepare(&_stmt).await.unwrap();
+    let _stmt: &str = include_str!("./sql/ping/get_records.sql");
+    let stmt: Statement = client.prepare(&_stmt).await.unwrap();
 
-    let results = client
+    let results: Vec<Ping> = client
         .query(&stmt, &[])
         .await?
         .iter()
@@ -22,14 +21,12 @@ pub async fn get_ping_records(client: &Client) -> Result<Vec<Ping>, MyError> {
 
 // add ping record
 pub async fn add_ping_record(client: &Client, ping_info: Ping) -> Result<i64, MyError> {
-    let _stmt = include_str!("./sql/ping/add_record.sql");
-    let stmt = client.prepare(&_stmt).await.unwrap();
-
-    println!("statement: {:?}", stmt);
+    let _stmt: &str = include_str!("./sql/ping/add_record.sql");
+    let stmt: Statement = client.prepare(&_stmt).await.unwrap();
 
     let rows: Vec<Row> = client.query(&stmt, &[&ping_info.value]).await.unwrap();
 
-    let idx = rows[0].get(0);
+    let idx: i64 = rows[0].get(0);
 
     Ok(idx)
 }

src/db/sql/ping/get_records.sql

@@ -1 +1 @@
-SELECT $table_fields FROM ping;
+SELECT id, value, ts_created FROM ping;