Merge pull request #55 from JakeRoggenbuck/add-delete

Add delete

Author: JakeRoggenbuck

simple_tester.py

@@ -1,8 +1,8 @@
 from lstore.db import Database
 from lstore.query import Query
-from lstore import show_logo
+from lstore import print_logo
 
-show_logo()
+print_logo()
 
 db = Database()
 grades_table = db.create_table('Grades', 5, 0)
@@ -12,8 +12,17 @@
 
 for i in range(0, 10):
     rec = query.insert(10 + i, 93, 0, 0, 0)
-    recs.append(rec)
+    recs.append(10 + i)
 
 for rec in recs:
-    vals = query.select(rec.rid, 0, [0])
+    vals = query.select(rec, 0, [0])
+    print(vals)
+
+for rec in recs:
+    if rec % 2 == 0:
+        print(f"Deleting {rec}")
+        query.delete(rec)
+
+for rec in recs:
+    vals = query.select(rec, 0, [0])
     print(vals)

src/database.rs

@@ -106,6 +106,10 @@ impl RTable {
         }
     }
 
+    pub fn delete(&mut self, rid: u64) {
+        self.page_directory.remove(&rid);
+    }
+
     fn _merge() {
         unreachable!("Not used in milestone 1")
     }

src/query.rs

@@ -13,9 +13,8 @@ impl RQuery {
         RQuery { table }
     }
 
-    fn delete(&mut self, primary_key: i64) {
-        // Delete the value in each column where the id == primary_key
-        // i.e. delete the whole record
+    fn delete(&mut self, primary_key: u64) {
+        self.table.delete(primary_key)
     }
 
     fn insert(&mut self, values: Vec<u64>) -> Record {
@@ -27,8 +26,8 @@ impl RQuery {
         search_key: i64,
         _search_key_index: i64,
         _projected_columns_index: Vec<i64>,
-    ) -> Vec<u64> {
-        self.table.read(search_key as u64).unwrap()
+    ) -> Option<Vec<u64>> {
+        self.table.read(search_key as u64)
     }
 
     fn select_version(&mut self) {}