Issue:
Bug: refactor(dynamic_routing): change insert operation to upsert for dynamic_routing_stats



## Description
<!-- Describe your changes in detail -->
So previously we were only inserting in dynamic_routing_stats table, after this change we will be doing an Upsert operation instead of directly performing an insert operation.

Pull request description:
## Type of Change
<!-- Put an `x` in the boxes that apply -->

- [ ] Bugfix
- [ ] New feature
- [ ] Enhancement
- [ ] Refactoring
- [ ] Dependency updates
- [ ] Documentation
- [ ] CI/CD

## Description
<!-- Describe your changes in detail -->
So previously we were only inserting in dynamic_routing_stats table, after this change we will be doing an Upsert operation instead of directly performing an insert operation.

### Additional Changes

- [ ] This PR modifies the API contract
- [ ] This PR modifies the database schema
- [ ] This PR modifies application configuration/environment variables

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1. `config`
2. `crates/router/src/configs`
3. `loadtest/config`
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## Motivation and Context
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## How did you test it?
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Did you write an integration/unit/API test to verify the code changes?
Or did you test this change manually (provide relevant screenshots)?
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The same flow is required, the way we test dynamic routing:
1. enable SR for a merchant.
2. set volume of payments to 100 for dynamic routing
3. make two consecutive payments(insure they end up in terminal state).
4. check the table `dynami_routing stats` for entry of both of them.


![Screenshot 2025-03-17 at 5 08 53 PM](https://github.com/user-attachments/assets/4cda988d-117c-45e5-9b5b-4dd8ff730ae5)

## Checklist
<!-- Put an `x` in the boxes that apply -->

- [ ] I formatted the code `cargo +nightly fmt --all`
- [ ] I addressed lints thrown by `cargo clippy`
- [ ] I reviewed the submitted code
- [ ] I added unit tests for my changes where possible


Testing:


The same flow is required, the way we test dynamic routing:
1. enable SR for a merchant.
2. set volume of payments to 100 for dynamic routing
3. make two consecutive payments(insure they end up in terminal state).
4. check the table `dynami_routing stats` for entry of both of them.


![Screenshot 2025-03-17 at 5 08 53 PM](https://github.com/user-attachments/assets/4cda988d-117c-45e5-9b5b-4dd8ff730ae5)

Patch:
diff --git a/crates/diesel_models/src/dynamic_routing_stats.rs b/crates/diesel_models/src/dynamic_routing_stats.rs
index 90cf4689080..f60db1e9fbf 100644
--- a/crates/diesel_models/src/dynamic_routing_stats.rs
+++ b/crates/diesel_models/src/dynamic_routing_stats.rs
@@ -1,4 +1,4 @@
-use diesel::{Insertable, Queryable, Selectable};
+use diesel::{AsChangeset, Identifiable, Insertable, Queryable, Selectable};
 
 use crate::schema::dynamic_routing_stats;
 
@@ -23,8 +23,8 @@ pub struct DynamicRoutingStatsNew {
     pub global_success_based_connector: Option<String>,
 }
 
-#[derive(Clone, Debug, Eq, PartialEq, Queryable, Selectable, Insertable)]
-#[diesel(table_name = dynamic_routing_stats, primary_key(payment_id), check_for_backend(diesel::pg::Pg))]
+#[derive(Clone, Debug, Eq, PartialEq, Identifiable, Queryable, Selectable, Insertable)]
+#[diesel(table_name = dynamic_routing_stats, primary_key(attempt_id, merchant_id), check_for_backend(diesel::pg::Pg))]
 pub struct DynamicRoutingStats {
     pub payment_id: common_utils::id_type::PaymentId,
     pub attempt_id: String,
@@ -43,3 +43,21 @@ pub struct DynamicRoutingStats {
     pub payment_method_type: Option<common_enums::PaymentMethodType>,
     pub global_success_based_connector: Option<String>,
 }
+
+#[derive(
+    Clone, Debug, Eq, PartialEq, AsChangeset, router_derive::DebugAsDisplay, serde::Deserialize,
+)]
+#[diesel(table_name = dynamic_routing_stats)]
+pub struct DynamicRoutingStatsUpdate {
+    pub amount: common_utils::types::MinorUnit,
+    pub success_based_routing_connector: String,
+    pub payment_connector: String,
+    pub currency: Option<common_enums::Currency>,
+    pub payment_method: Option<common_enums::PaymentMethod>,
+    pub capture_method: Option<common_enums::CaptureMethod>,
+    pub authentication_type: Option<common_enums::AuthenticationType>,
+    pub payment_status: common_enums::AttemptStatus,
+    pub conclusive_classification: common_enums::SuccessBasedRoutingConclusiveState,
+    pub payment_method_type: Option<common_enums::PaymentMethodType>,
+    pub global_success_based_connector: Option<String>,
+}
diff --git a/crates/diesel_models/src/query/dynamic_routing_stats.rs b/crates/diesel_models/src/query/dynamic_routing_stats.rs
index f6771cd103d..bf4cd706a69 100644
--- a/crates/diesel_models/src/query/dynamic_routing_stats.rs
+++ b/crates/diesel_models/src/query/dynamic_routing_stats.rs
@@ -1,6 +1,13 @@
+use diesel::{associations::HasTable, BoolExpressionMethods, ExpressionMethods};
+use error_stack::report;
+
 use super::generics;
 use crate::{
-    dynamic_routing_stats::{DynamicRoutingStats, DynamicRoutingStatsNew},
+    dynamic_routing_stats::{
+        DynamicRoutingStats, DynamicRoutingStatsNew, DynamicRoutingStatsUpdate,
+    },
+    errors,
+    schema::dynamic_routing_stats::dsl,
     PgPooledConn, StorageResult,
 };
 
@@ -9,3 +16,46 @@ impl DynamicRoutingStatsNew {
         generics::generic_insert(conn, self).await
     }
 }
+
+impl DynamicRoutingStats {
+    pub async fn find_optional_by_attempt_id_merchant_id(
+        conn: &PgPooledConn,
+        attempt_id: String,
+        merchant_id: &common_utils::id_type::MerchantId,
+    ) -> StorageResult<Option<Self>> {
+        generics::generic_find_one_optional::<<Self as HasTable>::Table, _, _>(
+            conn,
+            dsl::merchant_id
+                .eq(merchant_id.to_owned())
+                .and(dsl::attempt_id.eq(attempt_id.to_owned())),
+        )
+        .await
+    }
+
+    pub async fn update(
+        conn: &PgPooledConn,
+        attempt_id: String,
+        merchant_id: &common_utils::id_type::MerchantId,
+        dynamic_routing_stat: DynamicRoutingStatsUpdate,
+    ) -> StorageResult<Self> {
+        generics::generic_update_with_results::<
+            <Self as HasTable>::Table,
+            DynamicRoutingStatsUpdate,
+            _,
+            _,
+        >(
+            conn,
+            dsl::merchant_id
+                .eq(merchant_id.to_owned())
+                .and(dsl::attempt_id.eq(attempt_id.to_owned())),
+            dynamic_routing_stat,
+        )
+        .await?
+        .first()
+        .cloned()
+        .ok_or_else(|| {
+            report!(errors::DatabaseError::NotFound)
+                .attach_printable("Error while updating dynamic_routing_stats entry")
+        })
+    }
+}
diff --git a/crates/router/src/core/routing/helpers.rs b/crates/router/src/core/routing/helpers.rs
index 1d40039e2a3..e80ddbead4c 100644
--- a/crates/router/src/core/routing/helpers.rs
+++ b/crates/router/src/core/routing/helpers.rs
@@ -14,7 +14,7 @@ use common_utils::ext_traits::ValueExt;
 use common_utils::{ext_traits::Encode, id_type, types::keymanager::KeyManagerState};
 use diesel_models::configs;
 #[cfg(all(feature = "v1", feature = "dynamic_routing"))]
-use diesel_models::dynamic_routing_stats::DynamicRoutingStatsNew;
+use diesel_models::dynamic_routing_stats::{DynamicRoutingStatsNew, DynamicRoutingStatsUpdate};
 #[cfg(all(feature = "dynamic_routing", feature = "v1"))]
 use diesel_models::routing_algorithm;
 use error_stack::ResultExt;
@@ -821,28 +821,6 @@ pub async fn push_metrics_with_update_window_for_success_based_routing(
                 first_merchant_success_based_connector_label.to_string(),
             );
 
-            let dynamic_routing_stats = DynamicRoutingStatsNew {
-                payment_id: payment_attempt.payment_id.to_owned(),
-                attempt_id: payment_attempt.attempt_id.clone(),
-                merchant_id: payment_attempt.merchant_id.to_owned(),
-                profile_id: payment_attempt.profile_id.to_owned(),
-                amount: payment_attempt.get_total_amount(),
-                success_based_routing_connector: first_merchant_success_based_connector_label
-                    .to_string(),
-                payment_connector: payment_connector.to_string(),
-                payment_method_type: payment_attempt.payment_method_type,
-                currency: payment_attempt.currency,
-                payment_method: payment_attempt.payment_method,
-                capture_method: payment_attempt.capture_method,
-                authentication_type: payment_attempt.authentication_type,
-                payment_status: payment_attempt.status,
-                conclusive_classification: outcome,
-                created_at: common_utils::date_time::now(),
-                global_success_based_connector: Some(
-                    first_global_success_based_connector.label.to_string(),
-                ),
-            };
-
             core_metrics::DYNAMIC_SUCCESS_BASED_ROUTING.add(
                 1,
                 router_env::metric_attributes!(
@@ -915,12 +893,74 @@ pub async fn push_metrics_with_update_window_for_success_based_routing(
             );
             logger::debug!("successfully pushed success_based_routing metrics");
 
-            state
+            let duplicate_stats = state
                 .store
-                .insert_dynamic_routing_stat_entry(dynamic_routing_stats)
+                .find_dynamic_routing_stats_optional_by_attempt_id_merchant_id(
+                    payment_attempt.attempt_id.clone(),
+                    &payment_attempt.merchant_id.to_owned(),
+                )
                 .await
                 .change_context(errors::ApiErrorResponse::InternalServerError)
-                .attach_printable("Unable to push dynamic routing stats to db")?;
+                .attach_printable("Failed to fetch dynamic_routing_stats entry")?;
+
+            if duplicate_stats.is_some() {
+                let dynamic_routing_update = DynamicRoutingStatsUpdate {
+                    amount: payment_attempt.get_total_amount(),
+                    success_based_routing_connector: first_merchant_success_based_connector_label
+                        .to_string(),
+                    payment_connector: payment_connector.to_string(),
+                    payment_method_type: payment_attempt.payment_method_type,
+                    currency: payment_attempt.currency,
+                    payment_method: payment_attempt.payment_method,
+                    capture_method: payment_attempt.capture_method,
+                    authentication_type: payment_attempt.authentication_type,
+                    payment_status: payment_attempt.status,
+                    conclusive_classification: outcome,
+                    global_success_based_connector: Some(
+                        first_global_success_based_connector.label.to_string(),
+                    ),
+                };
+
+                state
+                    .store
+                    .update_dynamic_routing_stats(
+                        payment_attempt.attempt_id.clone(),
+                        &payment_attempt.merchant_id.to_owned(),
+                        dynamic_routing_update,
+                    )
+                    .await
+                    .change_context(errors::ApiErrorResponse::InternalServerError)
+                    .attach_printable("Unable to update dynamic routing stats to db")?;
+            } else {
+                let dynamic_routing_stats = DynamicRoutingStatsNew {
+                    payment_id: payment_attempt.payment_id.to_owned(),
+                    attempt_id: payment_attempt.attempt_id.clone(),
+                    merchant_id: payment_attempt.merchant_id.to_owned(),
+                    profile_id: payment_attempt.profile_id.to_owned(),
+                    amount: payment_attempt.get_total_amount(),
+                    success_based_routing_connector: first_merchant_success_based_connector_label
+                        .to_string(),
+                    payment_connector: payment_connector.to_string(),
+                    payment_method_type: payment_attempt.payment_method_type,
+                    currency: payment_attempt.currency,
+                    payment_method: payment_attempt.payment_method,
+                    capture_method: payment_attempt.capture_method,
+                    authentication_type: payment_attempt.authentication_type,
+                    payment_status: payment_attempt.status,
+                    conclusive_classification: outcome,
+                    created_at: common_utils::date_time::now(),
+                    global_success_based_connector: Some(
+                        first_global_success_based_connector.label.to_string(),
+                    ),
+                };
+
+                state
+                    .store
+                    .insert_dynamic_routing_stat_entry(dynamic_routing_stats)
+                    .await
+                    .change_context(errors::ApiErrorResponse::InternalServerError)
+                    .attach_printable("Unable to push dynamic routing stats to db")?;
+            };
 
             client
                 .update_success_rate(
diff --git a/crates/router/src/db/dynamic_routing_stats.rs b/crates/router/src/db/dynamic_routing_stats.rs
index d22f4fdd40b..f78655db0b3 100644
--- a/crates/router/src/db/dynamic_routing_stats.rs
+++ b/crates/router/src/db/dynamic_routing_stats.rs
@@ -16,6 +16,19 @@ pub trait DynamicRoutingStatsInterface {
         &self,
         dynamic_routing_stat_new: storage::DynamicRoutingStatsNew,
     ) -> CustomResult<storage::DynamicRoutingStats, errors::StorageError>;
+
+    async fn find_dynamic_routing_stats_optional_by_attempt_id_merchant_id(
+        &self,
+        attempt_id: String,
+        merchant_id: &common_utils::id_type::MerchantId,
+    ) -> CustomResult<Option<storage::DynamicRoutingStats>, errors::StorageError>;
+
+    async fn update_dynamic_routing_stats(
+        &self,
+        attempt_id: String,
+        merchant_id: &common_utils::id_type::MerchantId,
+        data: storage::DynamicRoutingStatsUpdate,
+    ) -> CustomResult<storage::DynamicRoutingStats, errors::StorageError>;
 }
 
 #[async_trait::async_trait]
@@ -31,6 +44,33 @@ impl DynamicRoutingStatsInterface for Store {
             .await
             .map_err(|error| report!(errors::StorageError::from(error)))
     }
+
+    async fn find_dynamic_routing_stats_optional_by_attempt_id_merchant_id(
+        &self,
+        attempt_id: String,
+        merchant_id: &common_utils::id_type::MerchantId,
+    ) -> CustomResult<Option<storage::DynamicRoutingStats>, errors::StorageError> {
+        let conn = connection::pg_connection_write(self).await?;
+        storage::DynamicRoutingStats::find_optional_by_attempt_id_merchant_id(
+            &conn,
+            attempt_id,
+            merchant_id,
+        )
+        .await
+        .map_err(|error| report!(errors::StorageError::from(error)))
+    }
+
+    async fn update_dynamic_routing_stats(
+        &self,
+        attempt_id: String,
+        merchant_id: &common_utils::id_type::MerchantId,
+        data: storage::DynamicRoutingStatsUpdate,
+    ) -> CustomResult<storage::DynamicRoutingStats, errors::StorageError> {
+        let conn = connection::pg_connection_write(self).await?;
+        storage::DynamicRoutingStats::update(&conn, attempt_id, merchant_id, data)
+            .await
+            .map_err(|error| report!(errors::StorageError::from(error)))
+    }
 }
 
 #[async_trait::async_trait]
@@ -42,6 +82,23 @@ impl DynamicRoutingStatsInterface for MockDb {
     ) -> CustomResult<storage::DynamicRoutingStats, errors::StorageError> {
         Err(errors::StorageError::MockDbError)?
     }
+
+    async fn find_dynamic_routing_stats_optional_by_attempt_id_merchant_id(
+        &self,
+        _attempt_id: String,
+        _merchant_id: &common_utils::id_type::MerchantId,
+    ) -> CustomResult<Option<storage::DynamicRoutingStats>, errors::StorageError> {
+        Err(errors::StorageError::MockDbError)?
+    }
+
+    async fn update_dynamic_routing_stats(
+        &self,
+        _attempt_id: String,
+        _merchant_id: &common_utils::id_type::MerchantId,
+        _data: storage::DynamicRoutingStatsUpdate,
+    ) -> CustomResult<storage::DynamicRoutingStats, errors::StorageError> {
+        Err(errors::StorageError::MockDbError)?
+    }
 }
 
 #[async_trait::async_trait]
@@ -55,4 +112,25 @@ impl DynamicRoutingStatsInterface for KafkaStore {
             .insert_dynamic_routing_stat_entry(dynamic_routing_stat)
             .await
     }
+
+    async fn find_dynamic_routing_stats_optional_by_attempt_id_merchant_id(
+        &self,
+        attempt_id: String,
+        merchant_id: &common_utils::id_type::MerchantId,
+    ) -> CustomResult<Option<storage::DynamicRoutingStats>, errors::StorageError> {
+        self.diesel_store
+            .find_dynamic_routing_stats_optional_by_attempt_id_merchant_id(attempt_id, merchant_id)
+            .await
+    }
+
+    async fn update_dynamic_routing_stats(
+        &self,
+        attempt_id: String,
+        merchant_id: &common_utils::id_type::MerchantId,
+        data: storage::DynamicRoutingStatsUpdate,
+    ) -> CustomResult<storage::DynamicRoutingStats, errors::StorageError> {
+        self.diesel_store
+            .update_dynamic_routing_stats(attempt_id, merchant_id, data)
+            .await
+    }
 }
diff --git a/crates/router/src/types/storage/dynamic_routing_stats.rs b/crates/router/src/types/storage/dynamic_routing_stats.rs
index ba692a25255..2b1bc3f4a45 100644
--- a/crates/router/src/types/storage/dynamic_routing_stats.rs
+++ b/crates/router/src/types/storage/dynamic_routing_stats.rs
@@ -1 +1,3 @@
-pub use diesel_models::dynamic_routing_stats::{DynamicRoutingStats, DynamicRoutingStatsNew};
+pub use diesel_models::dynamic_routing_stats::{
+    DynamicRoutingStats, DynamicRoutingStatsNew, DynamicRoutingStatsUpdate,
+};