Aggregate Data

database/Cargo.toml

@@ -7,3 +7,4 @@ edition = "2021"
 shared = { path = "../shared" }
 rusqlite = "0.31.0"
 postgres = "0.19.7"
+csv = "1.3.0"

database/artist.csv

@@ -0,0 +1,21 @@
+DisplayName,Nationality,Gender
+Charles Arnoldi,American,male
+David Aronson,American,male
+Irene Aronson,American,female
+Jean Arp,French,male
+Richard Artschwager,American,male
+Ruth Asawa,American,female
+Charles Robert Ashbee,British,male
+Erik Gunnar Asplund,Swedish,male
+Genevieve Asse,French,female
+Alvar Aalto,Finnish,male
+Aino Aalto,Finnish,female
+Eero Aarnio,Finnish,male
+Magdalena Abakanowicz,Polish,female
+James Abbe,American,male
+Berenice Abbott,American,female
+Robert Abel,American,male
+Raimund Abraham,American,male
+Ivor Abrahams,British,male
+Rodolfo Abularach,Guatemalan,male
+Vito Acconci,American,male

database/src/postgres.rs

@@ -1,4 +1,6 @@
+use csv::ReaderBuilder;
 use postgres::{Client, Error, NoTls};
+use std::fs::File;
 
 /// Create a new database.
 ///
@@ -180,3 +182,76 @@ pub fn insert_data(connection_string: &str, data: Vec<&str>) -> Result<(), Error
 
     Ok(())
 }
+
+/// Create a new database from a CSV file.
+///
+/// # Arguments
+///
+/// * `connection_string` - A connection string to the PostgreSQL server.
+/// * `db` - The name of the database to create.
+/// * `file_path` - The path to the CSV file.
+///
+/// # Returns
+///
+/// A `Result` indicating whether the operation was successful.
+///
+/// # Example
+///
+/// ```ignore
+/// use database::create_db_from_csv;
+///
+/// let connection_string = "postgresql://postgres:@localhost";
+/// let db_name = "moma";
+/// let file_path = "artist.csv";
+/// let table_name = "artist";
+///
+/// let result = create_db_from_csv(connection_string, db_name, file_path, table_name);
+/// assert!(result.is_ok());
+/// ```
+pub fn create_db_from_csv(
+    connection_string: &str,
+    db: &str,
+    file_path: &str,
+    table_name: &str,
+) -> Result<(), Error> {
+    create_db(connection_string, db)?;
+
+    let file = File::open(file_path).unwrap();
+    let mut rdr = ReaderBuilder::new().has_headers(true).from_reader(file);
+
+    let headers = rdr.headers().unwrap().clone();
+
+    let columns: Vec<String> = headers
+        .iter()
+        .map(|h| format!("{} VARCHAR NULL", h.replace(" ", "_")))
+        .collect();
+
+    let columns_clean: Vec<String> = headers.iter().map(|h| h.replace(" ", "_")).collect();
+
+    let create_table_query = format!(
+        "CREATE TABLE IF NOT EXISTS {} (id SERIAL PRIMARY KEY,{})",
+        table_name,
+        columns.join(", ")
+    );
+
+    let connection_string_full = format!("{}/{}", connection_string, db);
+    let mut client = Client::connect(&connection_string_full, NoTls)?;
+    client.batch_execute(&create_table_query)?;
+
+    for result in rdr.records() {
+        let record = result.unwrap();
+        let values: Vec<String> = record
+            .iter()
+            .map(|v| format!("'{}'", v.replace("'", "''")))
+            .collect();
+        let insert_query = format!(
+            "INSERT INTO {} ({}) VALUES ({})",
+            table_name,
+            columns_clean.join(", "),
+            values.join(", ")
+        );
+        client.batch_execute(&insert_query)?;
+    }
+
+    Ok(())
+}

database/tests/tests_postgres.rs

@@ -1,4 +1,4 @@
-use database::{add_tables, create_db, delete_db, insert_data};
+use database::{add_tables, create_db, create_db_from_csv, delete_db, insert_data};
 use postgres::{Client, Error, NoTls};
 use std::collections::HashMap;
 
@@ -122,4 +122,39 @@ mod tests_postgres {
 
         let _ = fixture_delete_db(&connection_string, &db_name);
     }
+
+    #[test]
+    #[ignore]
+    fn test_create_db_from_csv() {
+        let connection_string = "postgresql://postgres:@localhost";
+        let db_name = "moma";
+        let file_path = "artist.csv";
+        let table_name = "artist";
+
+        let _ = fixture_delete_db(&connection_string, &db_name);
+
+        let result = create_db_from_csv(connection_string, db_name, file_path, table_name);
+        assert!(result.is_ok());
+
+        let connection_string_full = format!("{}/{}", connection_string, db_name);
+        let mut client = Client::connect(&connection_string_full, NoTls).unwrap();
+
+        for row in client
+            .query(
+                "SELECT Nationality, COUNT(Nationality) AS Count 
+                FROM artist GROUP BY Nationality ORDER BY Count DESC",
+                &[],
+            )
+            .unwrap()
+        {
+            let (nationality, count): (Option<String>, Option<i64>) = (row.get(0), row.get(1));
+
+            assert!(nationality.is_some());
+            assert!(count.is_some());
+            println!("{:?} {:?}", nationality, count);
+        }
+
+        client.close().unwrap();
+        let _ = fixture_delete_db(&connection_string, &db_name);
+    }
 }