feat: database methods to compute percentiles on analysis records

db/db-sqlx-postgres/src/lib.rs

@@ -1227,6 +1227,59 @@ impl MCDatabase for Database {
             Ok(res.nonce as u32)
         }
     }
+
+    /// Get number of analytics entries that are under a certain duration
+    async fn stats_get_num_logs_under_time(&self, duration: u32) -> DBResult<usize> {
+
+    struct Count {
+        count: Option<i64>,
+    }
+
+    let count = sqlx::query_as!(
+        Count,
+        "SELECT COUNT(difficulty_factor) FROM mcaptcha_pow_analytics WHERE time <= $1;",
+        duration as i32,
+    )
+    .fetch_one(&self.pool)
+    .await
+    .map_err(|e| map_row_not_found_err(e, DBError::CaptchaNotFound))?;
+
+        Ok(count.count.unwrap_or_else(|| 0) as usize)
+    }
+
+    /// Get the entry at a location in the list of analytics entires under a certain time limit
+    /// and sorted in ascending order
+    async fn stats_get_entry_at_location_for_time_limit_asc(&self, duration: u32, location: u32) -> DBResult<Option<usize>> {
+
+
+        struct Difficulty {
+            difficulty_factor: Option<i32>,
+        }
+
+        match sqlx::query_as!(
+            Difficulty,
+            "SELECT
+            difficulty_factor
+        FROM
+            mcaptcha_pow_analytics
+        WHERE
+            time <= $1
+        ORDER BY difficulty_factor ASC LIMIT 1 OFFSET $2;",
+            duration as i32,
+            location as i64 - 1,
+        )
+        .fetch_one(&self.pool)
+        .await
+        {
+            Ok(res) => Ok(Some(res.difficulty_factor.unwrap() as usize)),
+            Err(sqlx::Error::RowNotFound) => Ok(None),
+            Err(e) => Err(map_row_not_found_err(e, DBError::CaptchaNotFound))
+
+        }
+
+
+    }
+
 }
 
 #[derive(Clone)]